Fix OAuth redirect_uri for local dev

- client_id always points to production so PDS can fetch metadata
- redirect_uri is dynamic (window.location.origin) so dev login
  redirects back to localhost instead of production
- Add localhost:5173/5174 to allowed redirect_uris in metadata

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

public/client-metadata.json

@@ -2,7 +2,11 @@
   "client_id": "https://coffee.apoena.dev/client-metadata.json",
   "client_name": "Coffee Map",
   "client_uri": "https://coffee.apoena.dev",
-  "redirect_uris": ["https://coffee.apoena.dev/oauth/callback"],
+  "redirect_uris": [
+    "https://coffee.apoena.dev/oauth/callback",
+    "http://localhost:5173/oauth/callback",
+    "http://localhost:5174/oauth/callback"
+  ],
   "grant_types": ["authorization_code", "refresh_token"],
   "response_types": ["code"],
   "scope": "atproto transition:generic",