Done4

[iwayemi5]

Add request caching to reduce duplicate API calls

Summary

This PR introduces an in-memory caching layer for frequently requested API endpoints to reduce redundant network requests and improve response times.

Changes

• Added a configurable request cache with TTL support.
• Cached responses for read-only GET endpoints.
• Invalidated cache entries after relevant data mutations.
• Added cache hit/miss logging for debugging.
• Updated documentation with cache configuration options.

Testing

• Verified cached responses are returned within the TTL window.
• Confirmed cache invalidation after create, update, and delete operations.
• Added unit tests for cache expiration and invalidation logic.
• Ran integration tests to ensure no regressions.

Notes

The cache is disabled by default in development and can be enabled through configuration. No breaking changes are introduced.

close #966