Add plugin usage telemetry (#14531)

adding metrics including: 
* plugin used
* plugin installed/uninstalled
* plugin enabled/disabled

codex-rs/app-server/src/message_processor.rs

@@ -39,6 +39,7 @@ use codex_app_server_protocol::ServerNotification;
 use codex_app_server_protocol::ServerRequestPayload;
 use codex_app_server_protocol::experimental_required_message;
 use codex_arg0::Arg0DispatchPaths;
+use codex_core::AnalyticsEventsClient;
 use codex_core::AuthManager;
 use codex_core::ThreadManager;
 use codex_core::auth::ExternalAuthRefreshContext;
@@ -191,6 +192,8 @@ impl MessageProcessor {
         auth_manager.set_external_auth_refresher(Arc::new(ExternalAuthRefreshBridge {
             outgoing: outgoing.clone(),
         }));
+        let analytics_events_client =
+            AnalyticsEventsClient::new(Arc::clone(&config), Arc::clone(&auth_manager));
         let thread_manager = Arc::new(ThreadManager::new(
             config.as_ref(),
             auth_manager.clone(),
@@ -201,6 +204,9 @@ impl MessageProcessor {
                     .enabled(codex_core::features::Feature::DefaultModeRequestUserInput),
             },
         ));
+        thread_manager
+            .plugins_manager()
+            .set_analytics_events_client(analytics_events_client.clone());
         // TODO(xl): Move into PluginManager once this no longer depends on config feature gating.
         thread_manager
             .plugins_manager()
@@ -223,6 +229,7 @@ impl MessageProcessor {
             loader_overrides,
             cloud_requirements,
             thread_manager,
+            analytics_events_client,
         );
         let external_agent_config_api = ExternalAgentConfigApi::new(config.codex_home.clone());