feat(dispatcher): use server-side incremental query (after=) from #26

- fetchEvents no longer reverses results (after= returns ASC)
- Watcher removes client-side id filtering (server handles it)
- Updated test mock to match ASC order

packages/dispatcher/src/ograph-client.ts

@@ -75,7 +75,6 @@ export class OGraphClient {
   async fetchEvents(ref: number, afterId?: number): Promise<OGraphEvent[]> {
     const { endpoint, token } = this.config.ograph;
     let url = `${endpoint}/events?ref=${ref}`;
-    // afterId 参数当前 API 可能不支持，先传着，API 忽略就拉全量
     if (afterId !== undefined) url += `&after=${afterId}`;
 
     const headers: Record<string, string> = {
@@ -97,9 +96,7 @@ export class OGraphClient {
       throw new Error(result.error ?? `HTTP ${response.status} fetching events`);
     }
 
-    // API 返回格式: { events: [...], total: N }
-    // 返回顺序: 降序（newest first），需要 reverse()
-    const events = result.events ?? [];
-    return events.reverse(); // 按 id 升序排列
+    // after= mode returns ASC order (oldest first), ideal for Dispatcher polling
+    return result.events ?? [];
   }
 }

packages/dispatcher/src/watcher.ts

@@ -70,15 +70,13 @@ export class ProjectionWatcher {
     const { agentId, eventTypes } = this.config.discovery!;
 
     try {
+      // Server-side incremental query: only returns events with id > lastSeenEventId
       const events = await this.client.fetchEvents(agentId, this.lastSeenEventId);
       
-      // 过滤：只取 id > lastSeenEventId 的（client-side，因为 API 可能不支持 after）
-      const newEvents = events.filter(e => e.id > this.lastSeenEventId);
-      
-      // 按 eventTypes 过滤（如果配置了）
+      // Filter by eventTypes (if configured)
       const filtered = eventTypes?.length 
-        ? newEvents.filter(e => eventTypes.includes(e.type_name))
-        : newEvents;
+        ? events.filter(e => eventTypes.includes(e.type_name))
+        : events;
       
       if (filtered.length > 0) {
         this.hasChanges = true;

packages/dispatcher/test/ograph-client.test.ts

@@ -46,9 +46,9 @@ describe('OGraphClient.fetchEvents', () => {
   it('fetches events for a ref and returns them in ascending order', async () => {
     const mockResponse = {
       events: [
-        { id: 3, type_hash: 'h3', type_name: 'task_created', payload: { id: 102 }, created_at: 3000 },
-        { id: 2, type_hash: 'h2', type_name: 'task_created', payload: { id: 101 }, created_at: 2000 },
         { id: 1, type_hash: 'h1', type_name: 'task_updated', payload: { id: 100 }, created_at: 1000 },
+        { id: 2, type_hash: 'h2', type_name: 'task_created', payload: { id: 101 }, created_at: 2000 },
+        { id: 3, type_hash: 'h3', type_name: 'task_created', payload: { id: 102 }, created_at: 3000 },
       ],
       total: 3,
     };