Switch from development callback URL to proper atproto-compliant private-use URI scheme (RFC 8252): - Scheme: social.coves:/callback (single slash per spec) - Works on both Android and iOS without Universal Links complexity Platform changes: - Android: Update CallbackActivity intent filter scheme - iOS: Update CFBundleURLSchemes in Info.plist - Remove taskAffinity from MainActivity (not needed) Dependencies: - Add flutter_web_auth_2 for browser-based OAuth - Remove atproto_oauth_flutter path dependency (to be deleted) 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>