fix(cache): resolve scanning stop issue and add cache TTL management

- Fix Redis SCAN cursor type conversion (Buffer to String) to prevent early termination
- Add progress logging in initializeClubCache (every 100 activities with summary)
- Add Redis memory limits (512MB with LRU eviction policy)
- Implement cache TTL: 24h for normal data, 1h for error states (allows retry)
- Fix Docker permission issue by running app container as root
- Add TTL configuration to .env and example.env

Root cause: SCAN cursor comparison failed due to type mismatch (Buffer vs String)
Impact: Scanning now processes all 5000+ IDs instead of stopping at ~300

.gitignore

@@ -1,5 +1,5 @@
 node_modules
-nkcs-engage.cookie.txt
+cookies.json
 .env
 redis_data
 warp