feat(agent): POST timeline events to vibn-frontend ingest API

- vibn-events-ingest.ts + emit() dual-write with session PATCH
- .env.example: VIBN_API_URL, AGENT_RUNNER_SECRET

Made-with: Cursor

dist/vibn-events-ingest.d.ts

@@ -0,0 +1,6 @@
+export interface IngestEventInput {
+    type: string;
+    payload?: Record<string, unknown>;
+    ts?: string;
+}
+export declare function ingestSessionEvents(vibnApiUrl: string, projectId: string, sessionId: string, events: IngestEventInput[]): Promise<void>;