Add query bar, maintenance panel, and heartbeat system

- Query bar with organized/grouped search results in portal
- Maintenance panel UI for triggering and viewing maintenance status
- Heartbeat service with periodic maintenance and dirty-tracking
- Query organizer for grouping search results by tag/kind/parent
- Slide-up animation for query panel

src/core/store.ts

@@ -25,6 +25,13 @@ function serializeEmbedding(embedding: number[]): Buffer {
   return Buffer.from(new Float32Array(embedding).buffer);
 }
 
+function notifyDirty(): void {
+  try {
+    const { markDirty } = require('../server/heartbeat');
+    markDirty();
+  } catch {}
+}
+
 export async function addNode(input: AddNodeInput): Promise<Node> {
   const db = getDb();
   const id = uuid();
@@ -52,6 +59,7 @@ export async function addNode(input: AddNodeInput): Promise<Node> {
     insertTag.run(id, tag);
   }
 
+  notifyDirty();
   return {
     id, kind: input.kind, title: input.title, content, status: input.status,
     tags, metadata, embedding, createdAt: now, updatedAt: now, lastAccessedAt: now, isStale: false,
@@ -149,6 +157,7 @@ export async function updateNode(id: string, input: UpdateNodeInput): Promise<No
     }
   }
 
+  notifyDirty();
   return getNode(id);
 }
 
@@ -159,6 +168,7 @@ export function removeNode(id: string, hard: boolean = false): boolean {
     return result.changes > 0;
   } else {
     const result = db.prepare('UPDATE nodes SET is_stale = 1, updated_at = ? WHERE id = ?').run(Date.now(), id);
+    if (result.changes > 0) notifyDirty();
     return result.changes > 0;
   }
 }