Change reconnectMu from sync.Mutex to sync.RWMutex so read operations can hold RLock during database access. This prevents reconnect() from closing the connection while queries are in progress. - GetIssue and SearchIssues now hold RLock during database operations - Close() acquires write lock to coordinate with reconnect - Add TestConcurrentReadsWithReconnect to verify the fix 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>