refactor(cli): simplify use-activity-query.ts (Commit 2.6)

- Create query-cache.ts module for cache management
- Create query-executor.ts for query execution with retry/dedup
- Create query-invalidation.ts for invalidation strategies
- Reduce use-activity-query.ts from ~480 to ~320 lines (-34%)
- Fix infinite retry loop and memory leak issues

Author: brandonkachen