fix: pass sessionKey to deliverOutboundPayloads for message:sent hook dispatch

Several call sites of deliverOutboundPayloads() were not passing the
sessionKey parameter, causing the internal message:sent hook to never
fire (the guard `if (!sessionKeyForInternalHooks) return` in deliver.ts
silently skipped the triggerInternalHook call).

Fixed call sites:
- commands/agent/delivery.ts (agent loop replies — main fix)
- infra/heartbeat-runner.ts (heartbeat OK + alert delivery)
- infra/outbound/message.ts (message tool sends)
- cron/isolated-agent/delivery-dispatch.ts (cron job delivery)
- gateway/server-node-events.ts (node event forwarding)

The sessionKey parameter already existed in DeliverOutboundPayloadsCoreParams
and was used by deliver.ts to emit the message:sent internal hook event,
but was simply not being passed from most callers.

src/commands/agent/delivery.ts

@@ -230,6 +230,7 @@ export async function deliverAgentCommandResult(params: {
         onError: (err) => logDeliveryError(err),
         onPayload: logPayload,
         deps: createOutboundSendDeps(deps),
+        sessionKey: opts.sessionKey,
       });
     }
   }

src/cron/isolated-agent/delivery-dispatch.ts

@@ -182,6 +182,7 @@ export async function dispatchCronDelivery(
         bestEffort: params.deliveryBestEffort,
         deps: createOutboundSendDeps(params.deps),
         abortSignal: params.abortSignal,
+        sessionKey: params.agentSessionKey,
       });
       delivered = deliveryResults.length > 0;
       return null;

src/gateway/server-node-events.ts

@@ -241,6 +241,7 @@ async function sendReceiptAck(params: {
     agentId,
     bestEffort: true,
     deps: createOutboundSendDeps(params.deps),
+    sessionKey: params.sessionKey,
   });
 }
 

src/infra/heartbeat-runner.ts

@@ -723,6 +723,7 @@ export async function runHeartbeatOnce(opts: {
       payloads: [{ text: heartbeatOkText }],
       agentId,
       deps: opts.deps,
+      sessionKey,
     });
     return true;
   };
@@ -928,6 +929,7 @@ export async function runHeartbeatOnce(opts: {
             ]),
       ],
       deps: opts.deps,
+      sessionKey,
     });
 
     // Record last delivered heartbeat payload for dedupe.

src/infra/outbound/message.ts

@@ -233,6 +233,7 @@ export async function sendMessage(params: MessageSendParams): Promise<MessageSen
             mediaUrls: mirrorMediaUrls.length ? mirrorMediaUrls : undefined,
           }
         : undefined,
+      sessionKey: params.mirror?.sessionKey,
     });
 
     return {