feat: wake agent via dispatchInboundMessage (in-process)

Use the same mechanism as Discord plugin — direct in-process call
to dispatchInboundMessageWithDispatcher from plugin-sdk. No WebSocket,
no CLI, no cron service dependency.

Creates unique session key per slot: agent:{agentId}:hf-calendar:slot-{slotId}

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

plugin/hooks/gateway-start.ts

@@ -7,20 +7,10 @@ export function registerGatewayStartHook(api: any, deps: {
   pushMetaToMonitor: () => Promise<void>;
   startCalendarScheduler: () => void;
   setMetaPushInterval: (handle: ReturnType<typeof setInterval>) => void;
-  onCronServiceAvailable?: (cron: any) => void;
 }) {
   const { logger, pushMetaToMonitor, startCalendarScheduler, setMetaPushInterval } = deps;
 
-  api.on('gateway_start', (event?: any) => {
-    // Extract cron service from gateway startup event (same as memory-core dreaming)
-    if (event && deps.onCronServiceAvailable) {
-      const context = event?.context;
-      const cron = context?.cron ?? context?.deps?.cron;
-      if (cron && typeof cron.add === 'function') {
-        deps.onCronServiceAvailable(cron);
-        logger.info('HarborForge: cron service acquired from gateway_start');
-      }
-    }
+  api.on('gateway_start', () => {
     logger.info('HarborForge plugin active');
     const live = getPluginConfig(api);