sloproxy

fix(runtime): skip deferred tools when injecting cache_control master

- Updated `ensureCacheControl` to inject cache_control into the last non-deferred tool instead of the last tool. - Adjusted `injectToolsCacheControl` to ignore tools marked with `defer_loading` for prompt caching. - Added unit tests to validate behavior for deferred tools, existing cache_control, and mixed tool arrays. Closes: #4561


+99 -14
2 changed files