feat(mcp): add GET /timers/sync-status endpoint (chronomind.syncStatus MCP tool)

backend/src/modules/timers/routes.ts

@@ -136,6 +136,34 @@ export async function timerRoutes(app: FastifyInstance) {
     return { success: true };
   });
 
+  // Sync status — returns timer + routine counts and latest sync timestamp.
+  // MCP tool: chronomind.syncStatus(userId) — instant ops visibility without querying raw data.
+  app.get('/timers/sync-status', async req => {
+    const auth = await extractAuth(req);
+    const { items: timers } = await repo.listTimers(auth.sub, PRODUCT_ID, {
+      limit: 1000,
+      offset: 0,
+      sortBy: 'createdAt',
+      sortOrder: 'desc',
+    });
+
+    const active = timers.filter(t => t.state === 'active' || t.state === 'warning').length;
+    const pending = timers.filter(t => t.state === 'paused').length;
+    const lastSyncedAt = timers[0]?.lastSyncedAt ?? null;
+    const conflictCount = timers.filter(t => t.syncVersion === 0).length;
+
+    return {
+      userId: auth.sub,
+      productId: PRODUCT_ID,
+      totalTimers: timers.length,
+      active,
+      pending,
+      conflictCount,
+      lastSyncedAt,
+      generatedAt: new Date().toISOString(),
+    };
+  });
+
   // Batch upsert (initial sync / offline queue flush)
   app.post('/timers/batch', async req => {
     const auth = await extractAuth(req);