Rebrand the entire application from "胡萝卜社区" (Carrot BBS) to "威友" (WithYou), including:

- Update app name, package name (skin.carrot.bbs → cn.qczlit.withyou), and bundle identifier
- Update API endpoints (bbs.littlelan.cn → withyou.littlelan.cn)
- Update URL scheme (carrotbbs:// → withyou://)
- Rename database from carrot_bbs to with_you
- Update CI/CD pipeline image names and artifact naming
- Add Android signing configuration for release builds
- Update all UI text and comments throughout the codebase
- Refactor registerStore to use in-memory state instead of AsyncStorage persistence
- Improve WebRTC track handling and call stream management
- Add metro platform resolution for native platform support

BREAKING app package, database, and URLs are no longer valid

metro.config.js

@@ -16,6 +16,9 @@ config.resolver.alias = {
   '@': path.resolve(__dirname, 'src'),
 };
 
+// Ensure platform-specific files are resolved correctly
+config.resolver.platforms = ['ios', 'android', 'native', 'web'];
+
 // NOTE: enhanceMiddleware is marked as deprecated in Metro's types,
 // but there's currently no official alternative for custom dev server headers.
 // For production, configure COEP/COOP headers on your hosting platform.