Summary

Replace the current App Password authentication with proper AT Protocol OAuth flow.

Current State

• Using App Password for authentication (development workaround)
• Not suitable for production use

Requirements

• Implement OAuth 2.0 flow as per AT Protocol spec
• Handle token refresh
• Secure session management
• Proper error handling for auth failures

Resources

• AT Protocol OAuth Spec
• Bluesky OAuth Documentation

Acceptance Criteria

• Users can authenticate via OAuth
• Sessions persist appropriately
• Token refresh works seamlessly
• App Password auth removed or deprecated