Allow injecting the Codex Apps tools cache (#33113)

## What changed

- Accept a caller-provided `CodexAppsToolsCache` when constructing a `ThreadManager` and pass it through to the MCP manager.
- Add `ConnectorRuntimeManager::new_without_cache()` for an in-memory runtime that neither loads nor persists connector state on disk.
- Re-export `CodexAppsToolsCache` from `codex-core` and `codex-core-api` for embedders.

## Testing

- Verify that a cache-disabled connector runtime ignores existing disk state and publishes live tools without creating cache files.

GitOrigin-RevId: f52f4f27c425a8d84ad0d0987b30a6fc3c14d702

codex-rs/core/src/agent/control_tests.rs

@@ -2338,6 +2338,7 @@ async fn resume_thread_subagent_restores_stored_metadata() {
         &config,
         auth_manager.clone(),
         crate::thread_manager::build_models_manager(&config, auth_manager),
+        crate::CodexAppsToolsCache::default(),
         SessionSource::Exec,
         Arc::new(codex_exec_server::EnvironmentManager::default_for_tests()),
         empty_extension_registry(),