fix(cron): pass heartbeat target=last for main-session cron jobs (#28508) (#28583)

* fix(cron): pass heartbeat target=last for main-session cron jobs

When a cron job with sessionTarget=main and wakeMode=now fires, it
triggers a heartbeat via runHeartbeatOnce. Since e2362d35 changed the
default heartbeat target from "last" to "none", these cron-triggered
heartbeats silently discard their responses instead of delivering them
to the last active channel (e.g. Telegram).

Fix: pass heartbeat: { target: "last" } from the cron timer to
runHeartbeatOnce for main-session jobs, and wire the override through
the gateway cron service builder. This restores delivery for
sessionTarget=main cron jobs without reverting the intentional default
change for regular heartbeats.

Regression introduced in: e2362d35 (2026-02-25)

Fixes #28508

* Cron: align server-cron wake routing expectations for main-target jobs

---------

Co-authored-by: Tak Hoffman <781889+Takhoffman@users.noreply.github.com>

src/gateway/server-cron.test.ts

@@ -40,7 +40,7 @@ describe("buildGatewayCronService", () => {
     fetchWithSsrFGuardMock.mockClear();
   });
 
-  it("canonicalizes non-agent sessionKey to agent store key for enqueue + wake", async () => {
+  it("routes main-target jobs to the main session for enqueue + wake", async () => {
     const tmpDir = path.join(os.tmpdir(), `server-cron-${Date.now()}`);
     const cfg = {
       session: {
@@ -73,12 +73,12 @@ describe("buildGatewayCronService", () => {
       expect(enqueueSystemEventMock).toHaveBeenCalledWith(
         "hello",
         expect.objectContaining({
-          sessionKey: "agent:main:discord:channel:ops",
+          sessionKey: "agent:main:main",
         }),
       );
       expect(requestHeartbeatNowMock).toHaveBeenCalledWith(
         expect.objectContaining({
-          sessionKey: "agent:main:discord:channel:ops",
+          sessionKey: undefined,
         }),
       );
     } finally {

src/gateway/server-cron.ts

@@ -182,11 +182,29 @@ export function buildGatewayCronService(params: {
     },
     runHeartbeatOnce: async (opts) => {
       const { runtimeConfig, agentId, sessionKey } = resolveCronWakeTarget(opts);
+      // Merge cron-supplied heartbeat overrides (e.g. target: "last") with the
+      // fully resolved agent heartbeat config so cron-triggered heartbeats
+      // respect agent-specific overrides (agents.list[].heartbeat) before
+      // falling back to agents.defaults.heartbeat.
+      const agentEntry =
+        Array.isArray(runtimeConfig.agents?.list) &&
+        runtimeConfig.agents.list.find(
+          (entry) =>
+            entry && typeof entry.id === "string" && normalizeAgentId(entry.id) === agentId,
+        );
+      const baseHeartbeat = {
+        ...runtimeConfig.agents?.defaults?.heartbeat,
+        ...agentEntry?.heartbeat,
+      };
+      const heartbeatOverride = opts?.heartbeat
+        ? { ...baseHeartbeat, ...opts.heartbeat }
+        : undefined;
       return await runHeartbeatOnce({
         cfg: runtimeConfig,
         reason: opts?.reason,
         agentId,
         sessionKey,
+        heartbeat: heartbeatOverride,
         deps: { ...params.deps, runtime: defaultRuntime },
       });
     },