Summary

Fixes #175. Addresses high CPU/RAM on app launch with 10 targeted performance fixes across 9 source files.

• RowProvider cache eviction: Replace O(n log n) sorted with O(n) filter in both InMemoryRowProvider and DatabaseRowProvider
• String indexing: Replace O(n) string.index(offsetBy:) with O(1) NSString.substring in GeometryWKBParser (3 methods), RedisDriver INFO parsing
• Autocomplete scoring: Replace O(n) label.count with O(1) NSString.length; hoist references.count out of inner loop in SQLSchemaProvider
• AppDelegate retry loops: Replace 5×200ms and 10×50ms polling loops with targeted delayed checks
• Storage init: Make QueryHistoryStorage.init non-blocking (queue.async); move TabStateStorage migration off main thread
• Health monitor stagger: Add 0–10s random initial delay to prevent all monitors pinging simultaneously at launch

Test plan

• Added 2 tests for RowProvider eviction correctness (closest rows retained, multi-cycle integrity)
• Added 1 test for shorter label scoring in SQLCompletionProvider
• Added 2 tests for allColumnsInScope prefix behavior in SQLSchemaProvider
• Added 1 test for staggered initial delay in ConnectionHealthMonitor
• All new tests pass
• Full build succeeds
• swiftlint lint --strict — 0 violations