fix(heartbeat,skills): 健康快照降级处理 + 技能加载重试

P1-3: health_snapshot 在 heartbeat engine 未初始化时不再报错，
返回 pending 状态快照，避免 HealthPanel 竞态报错。

P1-1: loadSkillsCatalog 新增 Path C 延迟重试（最多2次，间隔
1.5s/3s），解决 kernel 初始化未完成时 skills 返回空数组的问题。

desktop/src/store/configStore.ts

@@ -189,7 +189,7 @@ export interface ConfigActionsSlice {
     description?: string;
     enabled?: boolean;
   }) => Promise<ScheduledTask | undefined>;
-  loadSkillsCatalog: () => Promise<void>;
+  loadSkillsCatalog: (retryCount?: number) => Promise<void>;
   getSkill: (id: string) => Promise<SkillInfo | undefined>;
   createSkill: (skill: {
     name: string;
@@ -449,7 +449,7 @@ export const useConfigStore = create<ConfigStateSlice & ConfigActionsSlice>((set
 
   // === Skill Actions ===
 
-  loadSkillsCatalog: async () => {
+  loadSkillsCatalog: async (retryCount = 0) => {
     const client = get().client;
 
     // Path A: via injected client (KernelClient or GatewayClient)
@@ -494,10 +494,19 @@ export const useConfigStore = create<ConfigStateSlice & ConfigActionsSlice>((set
           source: ((s.source as string) || 'builtin') as 'builtin' | 'extra',
           path: s.path as string | undefined,
         })) });
+        return;
       }
     } catch (err) {
       console.warn('[configStore] skill_list direct invoke also failed:', err);
     }
+
+    // Path C: delayed retry — kernel may still be initializing
+    if (retryCount < 2) {
+      const delay = (retryCount + 1) * 1500; // 1.5s, 3s
+      console.log(`[configStore] Skills empty, retrying in ${delay}ms (attempt ${retryCount + 1}/2)`);
+      await new Promise((r) => setTimeout(r, delay));
+      return get().loadSkillsCatalog(retryCount + 1);
+    }
   },
 
   getSkill: async (id: string) => {