feat: add com.atproto.repo.describeRepo endpoint

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

Co-Authored-By: Claude Opus 4.5 <[e-mail]>

src/pds.js

···
   '/xrpc/com.atproto.repo.getRecord': {
     handler: (pds, req, url) => pds.handleGetRecord(url)
   },
+  '/xrpc/com.atproto.repo.describeRepo': {
+    handler: (pds, req, url) => pds.handleDescribeRepo()
+  },
   '/xrpc/com.atproto.sync.getLatestCommit': {
     handler: (pds, req, url) => pds.handleGetLatestCommit()
   },
···
     return Response.json({ uri, cid: row.cid, value })
   }
 
+  async handleDescribeRepo() {
+    const did = await this.getDid()
+    if (!did) {
+      return Response.json({ error: 'RepoNotFound', message: 'repo not found' }, { status: 404 })
+    }
+    const handle = await this.state.storage.get('handle')
+    // Get unique collections
+    const collections = this.sql.exec(
+      `SELECT DISTINCT collection FROM records`
+    ).toArray().map(r => r.collection)
+
+    return Response.json({
+      handle: handle || did,
+      did,
+      didDoc: {},
+      collections,
+      handleIsCorrect: !!handle
+    })
+  }
+
   handleGetLatestCommit() {
     const commits = this.sql.exec(
       `SELECT cid, rev FROM commits ORDER BY seq DESC LIMIT 1`
···
       }
     }
     return Response.json({ repos, cursor: undefined })
+  }
+
+  // describeRepo uses ?repo= param instead of ?did=
+  if (url.pathname === '/xrpc/com.atproto.repo.describeRepo') {
+    const repo = url.searchParams.get('repo')
+    if (!repo) {
+      return Response.json({ error: 'InvalidRequest', message: 'missing repo param' }, { status: 400 })
+    }
+    const id = env.PDS.idFromName(repo)
+    const pds = env.PDS.get(id)
+    return pds.fetch(request)
   }
 
   const did = url.searchParams.get('did')