Implement plan items: last repo persistence, remove folder selection, filter empty folders, separate repo selection URL

Backend changes:
- Add last_repo field to UserResponse in auth.go:27
- Update GetCurrentUser to include last_repo in response (auth.go:238)
- Update router to use POST /api/user/repo instead of /api/auth/last-repo (router.go:63)
- Implement empty folder filtering in github.go ListFiles function
- Add hasMatchingFiles helper to recursively check for matching files

Frontend changes:
- Simplify SetupWizard: remove 2-step wizard, default to root folder
- Add API call to save last_repo when completing setup
- Create new /select-repo page with SetupWizard component
- Update DashboardApp to check for last_repo from user data or URL params
- Redirect to /select-repo if no repo is configured
- Update 'Change repository' button to link to /select-repo
- Add last_repo field to User type in api.ts

This implements items 1-4 from the plan:
1. Save & Load Last Repo - Backend returns last_repo, frontend saves it via API
2. Remove Folder Selection - Setup wizard now single-step, defaults to root
3. Filter Empty Folders - Backend only returns folders with markdown files
4. Separate Repo Selection URL - New /select-repo page for repo selection

backend/internal/api/handlers/auth.go

···
 	Username  string `json:"username"`
 	AvatarURL string `json:"avatar_url"`
 	Provider  string `json:"provider"`
+	LastRepo  string `json:"last_repo"`
 }
 
 // min returns the minimum of two integers
···
 		Username:  user.Username,
 		AvatarURL: user.AvatarURL,
 		Provider:  "github",
+		LastRepo:  user.LastRepo,
 	}
 
 	w.Header().Set("Content-Type", "application/json")

backend/internal/api/router.go

···
 
 		r.Get("/api/auth/user", authHandler.GetCurrentUser)
 		r.Post("/api/auth/logout", authHandler.Logout)
-		r.Post("/api/auth/last-repo", authHandler.UpdateLastRepo)
+		r.Post("/api/user/repo", authHandler.UpdateLastRepo)
 
 		// Repository routes
 		r.Get("/api/repos", repoHandler.ListRepositories)

backend/internal/connectors/github.go

···
 				continue
 			}
 			node.Children = subNode.Children
+
+			// Skip empty directories (directories with no matching files)
+			if !hasMatchingFiles(&node, extensions) {
+				continue
+			}
 		}
 
 		root.Children = append(root.Children, node)
 	}
 
 	return root, nil
+}
+
+// hasMatchingFiles checks if a directory node contains any files (recursively)
+func hasMatchingFiles(node *FileNode, extensions []string) bool {
+	if node.Type == "file" {
+		// If extensions are specified, check if file matches
+		if len(extensions) > 0 {
+			ext := strings.TrimPrefix(filepath.Ext(node.Name), ".")
+			for _, allowedExt := range extensions {
+				if ext == allowedExt {
+					return true
+				}
+			}
+			return false
+		}
+		return true
+	}
+
+	if node.Type == "dir" {
+		for _, child := range node.Children {
+			if hasMatchingFiles(&child, extensions) {
+				return true
+			}
+		}
+	}
+
+	return false
 }
 
 // GetFileContent retrieves the content of a file

frontend/src/components/dashboard/DashboardApp.tsx

···
-import { useState } from 'react';
+import { useState, useEffect } from 'react';
 import { QueryClient, QueryClientProvider } from '@tanstack/react-query';
 import { Toaster } from 'sonner';
 import { Header } from '../layout/Header';
-import { SetupWizard } from './SetupWizard';
 import { FileTree } from './FileTree';
 import { EditorContainer } from '../editor/EditorContainer';
 import { useFiles } from '../../lib/hooks/useRepos';
···
   const [selectedFile, setSelectedFile] = useState<string | null>(null);
   const { data: user, isLoading: userLoading } = useCurrentUser();
 
+  // Check for last_repo or URL params and redirect if needed
+  useEffect(() => {
+    if (userLoading || !user) return;
+
+    // Check URL params first
+    const urlParams = new URLSearchParams(window.location.search);
+    const repoParam = urlParams.get('repo');
+
+    if (repoParam) {
+      // Parse repo from URL (format: owner/repo)
+      const [owner, repo] = repoParam.split('/');
+      if (owner && repo) {
+        setRepoConfig({ owner, repo, folder: '' });
+        return;
+      }
+    }
+
+    // Check user's last_repo
+    if (user.last_repo) {
+      const [owner, repo] = user.last_repo.split('/');
+      if (owner && repo) {
+        setRepoConfig({ owner, repo, folder: '' });
+        return;
+      }
+    }
+
+    // No repo configured, redirect to select-repo page
+    window.location.href = '/select-repo';
+  }, [user, userLoading]);
+
   const { data: filesData, isLoading: filesLoading } = useFiles(
     repoConfig?.owner || '',
     repoConfig?.repo || '',
···
     return null;
   }
 
-  // Show setup wizard if no repository is configured
+  // Show loading while checking for repo config
   if (!repoConfig) {
     return (
-      <SetupWizard
-        onComplete={(config) => {
-          setRepoConfig(config);
-          // TODO: Save config to database/localStorage
-        }}
-      />
+      <div className="min-h-screen bg-gray-50 flex items-center justify-center">
+        <Loading size="lg" text="Loading repository..." />
+      </div>
     );
   }
 
···
               )}
             </div>
             <button
-              onClick={() => setRepoConfig(null)}
+              onClick={() => window.location.href = '/select-repo'}
               className="mt-2 text-xs text-gray-600 hover:text-gray-900 underline"
             >
               Change repository

frontend/src/components/dashboard/SetupWizard.tsx

···
-import { useState, useEffect } from 'react';
+import { useState } from 'react';
 import { toast } from 'sonner';
 import { Button } from '../ui/button';
 import { useRepositories } from '../../lib/hooks/useRepos';
 import { apiClient } from '../../lib/api';
 
-interface SetupWizardProps {
-  onComplete: (config: {
-    owner: string;
-    repo: string;
-    folder: string;
-  }) => void;
-}
-
-interface FolderItem {
-  name: string;
-  path: string;
-  type: 'file' | 'dir';
-}
-
-export function SetupWizard({ onComplete }: SetupWizardProps) {
-  const [step, setStep] = useState(1);
+export function SetupWizard() {
   const [selectedRepoFullName, setSelectedRepoFullName] = useState('');
-  const [folder, setFolder] = useState('');
-  const [folders, setFolders] = useState<FolderItem[]>([]);
-  const [loadingFolders, setLoadingFolders] = useState(false);
   const [sortBy, setSortBy] = useState<'updated' | 'created' | 'name'>('updated');
+  const [isSubmitting, setIsSubmitting] = useState(false);
 
   // Fetch repositories
   const { data: repos, isLoading: reposLoading, error: reposError } = useRepositories(sortBy);
···
   // Parse owner and repo from selected repository
   const [owner, repo] = selectedRepoFullName ? selectedRepoFullName.split('/') : ['', ''];
 
-  // Fetch folders when we move to step 2
-  useEffect(() => {
-    if (step === 2 && owner && repo) {
-      fetchFolders('');
-    }
-  }, [step, owner, repo]);
+  const handleComplete = async () => {
+    if (!selectedRepoFullName) return;
 
-  const fetchFolders = async (path: string) => {
-    setLoadingFolders(true);
+    setIsSubmitting(true);
     try {
-      const response = await apiClient.get(`/api/repos/${owner}/${repo}/files`, {
-        params: { path, ref: '' }
+      // Save last_repo to user profile
+      await apiClient.post('/api/user/repo', {
+        last_repo: selectedRepoFullName,
       });
-      
-      // Filter to only show directories
-      const dirs = response.data.files
-        .filter((item: FolderItem) => item.type === 'dir')
-        .sort((a: FolderItem, b: FolderItem) => a.name.localeCompare(b.name));
-      
-      setFolders(dirs);
+
+      // Redirect to dashboard with repo parameter
+      window.location.href = `/dashboard?repo=${encodeURIComponent(selectedRepoFullName)}`;
     } catch (error) {
-      console.error('Failed to fetch folders:', error);
-      toast.error('Failed to load folders', {
+      console.error('Failed to save repository:', error);
+      toast.error('Failed to save repository', {
         description: error instanceof Error ? error.message : 'Please try again',
       });
-      setFolders([]);
-    } finally {
-      setLoadingFolders(false);
-    }
-  };
-
-  const handleNext = () => {
-    if (step === 1 && selectedRepoFullName) {
-      setStep(2);
-    } else if (step === 2) {
-      onComplete({ owner, repo, folder: folder || '' });
+      setIsSubmitting(false);
     }
-  };
-
-  const handleBack = () => {
-    setStep(step - 1);
   };
 
   return (
···
         </div>
 
         <div className="bg-white rounded-lg border border-gray-200 shadow-sm p-8">
-          {/* Progress Steps */}
-          <div className="flex items-center justify-center mb-8">
-            <div className="flex items-center">
-              <div
-                className={`w-8 h-8 rounded-full flex items-center justify-center ${
-                  step >= 1
-                    ? 'bg-gray-900 text-white'
-                    : 'bg-gray-200 text-gray-500'
-                }`}
-              >
-                1
-              </div>
-              <div
-                className={`w-24 h-0.5 ${
-                  step >= 2 ? 'bg-gray-900' : 'bg-gray-200'
-                }`}
-              ></div>
-              <div
-                className={`w-8 h-8 rounded-full flex items-center justify-center ${
-                  step >= 2
-                    ? 'bg-gray-900 text-white'
-                    : 'bg-gray-200 text-gray-500'
-                }`}
-              >
-                2
-              </div>
+          {/* Repository Selection */}
+          <div className="space-y-6">
+            <div>
+              <h2 className="text-xl font-bold text-gray-900 mb-4">
+                Select Your Repository
+              </h2>
+              <p className="text-sm text-gray-600 mb-6">
+                Choose the GitHub repository where your blog posts are stored.
+              </p>
             </div>
-          </div>
 
-          {/* Step 1: Repository Selection */}
-          {step === 1 && (
-            <div className="space-y-6">
-              <div>
-                <h2 className="text-xl font-bold text-gray-900 mb-4">
-                  Select Your primary Repository
-                </h2>
-                <p className="text-sm text-gray-600 mb-6">
-                  Choose the GitHub repository where your blog posts are stored.
-                </p>
+            <div className="space-y-4">
+              <div className="flex items-center justify-between mb-2">
+                <label className="block text-sm font-semibold text-gray-700">
+                  Repository
+                </label>
+                <select
+                  value={sortBy}
+                  onChange={(e) => setSortBy(e.target.value as any)}
+                  className="text-xs px-2 py-1 border border-gray-300 rounded-md focus:outline-none focus:ring-1 focus:ring-gray-900"
+                >
+                  <option value="updated">Recently Updated</option>
+                  <option value="created">Recently Created</option>
+                  <option value="name">Name</option>
+                </select>
               </div>
 
-              <div className="space-y-4">
-                <div className="flex items-center justify-between mb-2">
-                  <label className="block text-sm font-semibold text-gray-700">
-                    Repository
-                  </label>
-                  <select
-                    value={sortBy}
-                    onChange={(e) => setSortBy(e.target.value as any)}
-                    className="text-xs px-2 py-1 border border-gray-300 rounded-md focus:outline-none focus:ring-1 focus:ring-gray-900"
-                  >
-                    <option value="updated">Recently Updated</option>
-                    <option value="created">Recently Created</option>
-                    <option value="name">Name</option>
-                  </select>
-                </div>
-
-                {reposLoading ? (
-                  <div className="w-full px-4 py-12 border border-gray-300 rounded-md bg-gray-50">
-                    <div className="flex flex-col items-center justify-center">
-                      <div className="animate-spin rounded-full h-8 w-8 border-b-2 border-gray-900 mb-3"></div>
-                      <p className="text-sm text-gray-600">Loading your repositories...</p>
-                    </div>
-                  </div>
-                ) : reposError ? (
-                  <div className="w-full px-4 py-8 border border-red-300 rounded-md bg-red-50">
-                    <div className="text-center">
-                      <svg
-                        className="w-12 h-12 text-red-400 mx-auto mb-3"
-                        fill="none"
-                        viewBox="0 0 24 24"
-                        stroke="currentColor"
-                      >
-                        <path
-                          strokeLinecap="round"
-                          strokeLinejoin="round"
-                          strokeWidth={2}
-                          d="M12 8v4m0 4h.01M21 12a9 9 0 11-18 0 9 9 0 0118 0z"
-                        />
-                      </svg>
-                      <p className="text-sm text-red-800 font-semibold mb-1">Failed to load repositories</p>
-                      <p className="text-xs text-red-600">
-                        Make sure you've granted MarkEdit access to your repositories.
-                      </p>
-                    </div>
-                  </div>
-                ) : (
-                  <>
-                    <select
-                      value={selectedRepoFullName}
-                      onChange={(e) => setSelectedRepoFullName(e.target.value)}
-                      className="w-full px-4 py-3 border border-gray-300 rounded-md focus:outline-none focus:ring-2 focus:ring-gray-900 focus:border-transparent text-base"
-                    >
-                      <option value="">Choose a repository...</option>
-                      {repos?.map((repo) => (
-                        <option key={repo.id} value={repo.full_name}>
-                          {repo.full_name}
-                          {repo.private && ' 🔒'}
-                        </option>
-                      ))}
-                    </select>
-
-                    {repos && repos.length > 0 && (
-                      <p className="text-xs text-gray-500">
-                        {repos.length} {repos.length === 1 ? 'repository' : 'repositories'} found
-                      </p>
-                    )}
-
-                    {repos && repos.length === 0 && (
-                      <div className="p-4 bg-amber-50 rounded-lg border border-amber-200">
-                        <p className="text-sm text-amber-800">
-                          No repositories found. Make sure you've authorized MarkEdit to access your GitHub repositories.
-                        </p>
-                      </div>
-                    )}
-                  </>
-                )}
-
-                {selectedRepoFullName && (
-                  <div className="p-4 bg-gray-50 rounded-lg border border-gray-200">
-                    <div className="text-sm text-gray-700">
-                      <strong>Selected repository:</strong>
-                      <div className="mt-1 font-mono text-gray-900">
-                        github.com/{selectedRepoFullName}
-                      </div>
-                    </div>
+              {reposLoading ? (
+                <div className="w-full px-4 py-12 border border-gray-300 rounded-md bg-gray-50">
+                  <div className="flex flex-col items-center justify-center">
+                    <div className="animate-spin rounded-full h-8 w-8 border-b-2 border-gray-900 mb-3"></div>
+                    <p className="text-sm text-gray-600">Loading your repositories...</p>
                   </div>
-                )}
-              </div>
-            </div>
-          )}
-
-          {/* Step 2: Folder Configuration */}
-          {step === 2 && (
-            <div className="space-y-6">
-              <div>
-                <h2 className="text-xl font-bold text-gray-900 mb-4">
-                  Configure Folder Path
-                </h2>
-                <p className="text-sm text-gray-600 mb-6">
-                  Select which folder contains your blog posts, or leave empty to use the root directory.
-                </p>
-              </div>
-
-              <div className="space-y-4">
-                <div>
-                  <label className="block text-sm font-semibold text-gray-700 mb-2">
-                    Folder Path (optional)
-                  </label>
-
-                  {loadingFolders ? (
-                    <div className="w-full px-4 py-8 border border-gray-300 rounded-md bg-gray-50">
-                      <div className="flex flex-col items-center justify-center">
-                        <div className="animate-spin rounded-full h-6 w-6 border-b-2 border-gray-900 mb-2"></div>
-                        <p className="text-xs text-gray-600">Loading folders...</p>
-                      </div>
-                    </div>
-                  ) : (
-                    <>
-                      <select
-                        value={folder}
-                        onChange={(e) => setFolder(e.target.value)}
-                        className="w-full px-4 py-3 border border-gray-300 rounded-md focus:outline-none focus:ring-2 focus:ring-gray-900 focus:border-transparent text-base"
-                      >
-                        <option value="">📁 Root directory (all markdown files)</option>
-                        {folders.map((dir) => (
-                          <option key={dir.path} value={dir.path}>
-                            📁 {dir.path}
-                          </option>
-                        ))}
-                      </select>
-
-                      {folders.length === 0 && !loadingFolders && (
-                        <p className="mt-2 text-xs text-gray-500">
-                          No folders found in this repository. You can use the root directory.
-                        </p>
-                      )}
-
-                      {folders.length > 0 && (
-                        <p className="mt-2 text-xs text-gray-500">
-                          {folders.length} {folders.length === 1 ? 'folder' : 'folders'} found
-                        </p>
-                      )}
-                    </>
-                  )}
                 </div>
-
-                <div className="p-4 bg-amber-50 rounded-lg border border-amber-200">
-                  <div className="flex gap-3">
+              ) : reposError ? (
+                <div className="w-full px-4 py-8 border border-red-300 rounded-md bg-red-50">
+                  <div className="text-center">
                     <svg
-                      className="w-5 h-5 text-amber-600 flex-shrink-0 mt-0.5"
+                      className="w-12 h-12 text-red-400 mx-auto mb-3"
                       fill="none"
                       viewBox="0 0 24 24"
                       stroke="currentColor"
···
                         strokeLinecap="round"
                         strokeLinejoin="round"
                         strokeWidth={2}
-                        d="M13 16h-1v-4h-1m1-4h.01M21 12a9 9 0 11-18 0 9 9 0 0118 0z"
+                        d="M12 8v4m0 4h.01M21 12a9 9 0 11-18 0 9 9 0 0118 0z"
                       />
                     </svg>
-                    <div className="text-sm text-amber-800">
-                      <strong className="block mb-1">Note:</strong>
-                      <p>
-                        MarkEdit will search for markdown files (.md, .mdx) in the selected folder and all its subfolders.
-                      </p>
-                    </div>
+                    <p className="text-sm text-red-800 font-semibold mb-1">Failed to load repositories</p>
+                    <p className="text-xs text-red-600">
+                      Make sure you've granted MarkEdit access to your repositories.
+                    </p>
                   </div>
                 </div>
+              ) : (
+                <>
+                  <select
+                    value={selectedRepoFullName}
+                    onChange={(e) => setSelectedRepoFullName(e.target.value)}
+                    className="w-full px-4 py-3 border border-gray-300 rounded-md focus:outline-none focus:ring-2 focus:ring-gray-900 focus:border-transparent text-base"
+                    disabled={isSubmitting}
+                  >
+                    <option value="">Choose a repository...</option>
+                    {repos?.map((repo) => (
+                      <option key={repo.id} value={repo.full_name}>
+                        {repo.full_name}
+                        {repo.private && ' 🔒'}
+                      </option>
+                    ))}
+                  </select>
 
+                  {repos && repos.length > 0 && (
+                    <p className="text-xs text-gray-500">
+                      {repos.length} {repos.length === 1 ? 'repository' : 'repositories'} found
+                    </p>
+                  )}
+
+                  {repos && repos.length === 0 && (
+                    <div className="p-4 bg-amber-50 rounded-lg border border-amber-200">
+                      <p className="text-sm text-amber-800">
+                        No repositories found. Make sure you've authorized MarkEdit to access your GitHub repositories.
+                      </p>
+                    </div>
+                  )}
+                </>
+              )}
+
+              {selectedRepoFullName && (
                 <div className="p-4 bg-gray-50 rounded-lg border border-gray-200">
                   <div className="text-sm text-gray-700">
-                    <strong>MarkEdit will monitor:</strong>
+                    <strong>Selected repository:</strong>
                     <div className="mt-1 font-mono text-gray-900">
-                      {owner}/{repo}{folder ? `/${folder}` : ' (root)'}
+                      github.com/{selectedRepoFullName}
                     </div>
                   </div>
                 </div>
+              )}
+
+              <div className="p-4 bg-blue-50 rounded-lg border border-blue-200">
+                <div className="flex gap-3">
+                  <svg
+                    className="w-5 h-5 text-blue-600 flex-shrink-0 mt-0.5"
+                    fill="none"
+                    viewBox="0 0 24 24"
+                    stroke="currentColor"
+                  >
+                    <path
+                      strokeLinecap="round"
+                      strokeLinejoin="round"
+                      strokeWidth={2}
+                      d="M13 16h-1v-4h-1m1-4h.01M21 12a9 9 0 11-18 0 9 9 0 0118 0z"
+                    />
+                  </svg>
+                  <div className="text-sm text-blue-800">
+                    <strong className="block mb-1">Note:</strong>
+                    <p>
+                      MarkEdit will search for markdown files (.md, .mdx) in the entire repository.
+                    </p>
+                  </div>
+                </div>
               </div>
             </div>
-          )}
+          </div>
 
           {/* Navigation Buttons */}
-          <div className="flex items-center justify-between mt-8 pt-6 border-t border-gray-200">
+          <div className="flex items-center justify-end mt-8 pt-6 border-t border-gray-200">
             <Button
-              variant="outline"
-              onClick={handleBack}
-              disabled={step === 1}
-              className={step === 1 ? 'invisible' : ''}
-            >
-              Back
-            </Button>
-
-            <Button
-              onClick={handleNext}
-              disabled={
-                (step === 1 && !selectedRepoFullName) ||
-                (step === 1 && reposLoading)
-              }
+              onClick={handleComplete}
+              disabled={!selectedRepoFullName || reposLoading || isSubmitting}
               className="bg-gray-900 hover:bg-gray-800 text-white"
             >
-              {step === 1 ? 'Next' : 'Complete Setup'}
+              {isSubmitting ? 'Setting up...' : 'Complete Setup'}
             </Button>
           </div>
         </div>

frontend/src/lib/types/api.ts

···
   username: string;
   avatar_url: string;
   provider: string;
+  last_repo?: string;
 }
 
 export interface Repository {

frontend/src/pages/select-repo.astro

···
+---
+import '../styles/globals.css';
+import { SetupWizard } from '../components/dashboard/SetupWizard';
+---
+
+<html lang="en">
+	<head>
+		<meta charset="utf-8" />
+		<link rel="icon" type="image/svg+xml" href="/favicon.svg" />
+		<meta name="viewport" content="width=device-width" />
+		<meta name="generator" content={Astro.generator} />
+		<title>Select Repository - MarkEdit</title>
+		<link rel="preconnect" href="https://fonts.googleapis.com">
+		<link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
+		<link href="https://fonts.googleapis.com/css2?family=Archivo+Black&family=Crimson+Pro:wght@400;600&display=swap" rel="stylesheet">
+	</head>
+	<body>
+		<SetupWizard client:only="react" />
+	</body>
+</html>