fix(tauri): update @reserved annotations + remove dead SaaS client methods

- Update 9 @reserved → @connected for commands with frontend consumers:
  zclaw_status, zclaw_start, zclaw_stop, zclaw_restart, zclaw_doctor,
  viking_add_with_metadata, viking_store_with_summaries,
  trigger_execute, scheduled_task_create
- Remove 10 dead SaaS client methods with zero callers:
  healthCheck, listDevices (saas-client.ts)
  getRelayTask, getUsage/relay (saas-relay.ts)
  listPrompts, getPrompt, listPromptVersions, getPromptVersion (saas-prompt.ts)
  getPlan, getUsage/billing (saas-billing.ts)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

desktop/src-tauri/src/kernel_commands/trigger.rs

@@ -227,7 +227,7 @@ pub async fn trigger_delete(
 }
 
 /// Execute a trigger manually
-// @reserved: 暂无前端集成
+// @connected
 #[tauri::command]
 pub async fn trigger_execute(
     state: State<'_, KernelState>,