refactor: switch to pnpm workspaces

- Add pnpm-workspace.yaml
- Add .npmrc for pnpm settings
- Update all package.json to use pnpm commands
- Use workspace:* protocol for internal deps
- Move example TypeSpec files to typlex/ folder
- Update example to generate lexicons/ (alongside where schemas/ would go)

Structure:
- packages/emitter - @typlex/emitter
- packages/cli - @typlex/cli
- packages/example - @typlex/example
- typlex/ - TypeSpec source
- lexicons/ - Generated JSON (from typlex)
- schemas/ - Would be from @atproto/lexicon CLI

All tests passing (22/22)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <[e-mail]>

.npmrc

···
+# Use pnpm for this monorepo
+shamefully-hoist=true

package.json

···
   "version": "0.1.0",
   "private": true,
   "description": "TypeSpec-based IDL for ATProto Lexicons",
-  "workspaces": [
-    "packages/*"
-  ],
   "scripts": {
-    "build": "npm run build -w @typlex/emitter && npm run build -w @typlex/cli",
-    "test": "npm run test:ci -w @typlex/emitter",
-    "test:watch": "npm test -w @typlex/emitter",
-    "example": "npm run build -w @typlex/example",
-    "validate": "npm run build && npm run test && npm run example"
+    "build": "pnpm -r build",
+    "test": "pnpm --filter @typlex/emitter test",
+    "test:watch": "pnpm --filter @typlex/emitter test:watch",
+    "example": "pnpm --filter @typlex/example build",
+    "validate": "pnpm build && pnpm test"
   },
   "repository": {
     "type": "git",
···
     "idl"
   ],
   "author": "",
-  "license": "MIT"
+  "license": "MIT",
+  "devDependencies": {
+    "typescript": "^5.0.0"
+  }
 }

packages/example/package.json

···
   "private": true,
   "type": "module",
   "scripts": {
-    "typlex": "typlex main.tsp",
-    "build": "npm run typlex"
+    "build": "typlex typlex/main.tsp"
   },
   "dependencies": {
     "@typespec/compiler": "^0.64.0",
-    "@typlex/emitter": "*",
-    "@typlex/cli": "*"
+    "@typlex/emitter": "workspace:*",
+    "@typlex/cli": "workspace:*"
   },
   "devDependencies": {
     "typescript": "^5.0.0"

pnpm-lock.yaml

···
+lockfileVersion: '9.0'
+
+settings:
+  autoInstallPeers: true
+  excludeLinksFromLockfile: false
+
+importers:
+
+  .: {}

pnpm-workspace.yaml

···
+packages:
+  - 'packages/*'