Vote Service:
- Remove deleteVote method - backend handles toggle logic
- Remove getUserVotes - vote state now comes from feed viewer data
- Remove unused ExistingVote and VoteInfo classes
- Handle empty uri/cid response as successful toggle-off
- Use shared extractRkeyFromUri utility

Vote Provider:
- Remove existingVoteRkey/Direction params from createVote call
- Remove loadInitialVotes - replaced by setInitialVoteState per-post
- Add extractRkeyFromUri static utility to VoteState
- Clear score adjustments in setInitialVoteState to prevent double-counting

This aligns with the backend's vote cache approach where viewer state
is populated from PDS on each request rather than relying on the
eventually-consistent AppView index.

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

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

Add ViewerState class to represent the viewer's relationship with posts:
- vote: direction ("up", "down", or null)
- voteUri: AT-URI of the vote record
- saved: bookmark status
- tags: user-applied tags

This enables the feed to include viewer-specific state from the backend,
allowing proper initialization of vote UI state on feed refresh.

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

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

Major OAuth architecture rework - delegate complexity to backend.

Key changes:
- Add CovesSession model for simplified sealed tokens
- Add CovesAuthService for backend-delegated OAuth
- Update OAuth config for private-use URI scheme (RFC 8252)
- Add automatic token refresh on 401 responses
- Remove atproto_oauth_flutter package (~14K lines)

The backend now handles all OAuth complexity (DPoP, PKCE, token exchange)
and returns opaque sealed tokens that the client simply stores and sends.

- Remove unused imports in test files
- Add assertion on unused variable in singleton test
- Clean up redaction test file (remove unused mocks)

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

Auto-format all Dart files per CODE_QUALITY_GUIDE.md standards.

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

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

Update feed_screen_test.dart for the new OAuth patterns.

iOS changes:
- Add Runner.entitlements for associated domains
- Enable Universal Links (applinks:coves.social)
- Reference entitlements in Xcode project

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

Remove the client-side OAuth implementation now that auth is delegated
to the Coves backend. This eliminates ~14,000 lines of complex OAuth
code that handled:

Removed oauth_service.dart:
- Complex OAuthSession management
- Client-side token refresh
- DPoP key generation and proof signing
- PKCE code verifier/challenge generation

Removed atproto_oauth_flutter package:
- DPoP implementation (fetch_dpop.dart)
- Identity resolution (did/handle resolvers)
- OAuth server discovery and metadata
- Token exchange and refresh logic
- Cryptographic key management
- Session state persistence

The backend now handles all of this complexity, returning opaque
sealed tokens that the client simply stores and sends.

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

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