fix(telegram): cron and heartbeat messages land in wrong chat instead of target topic (#19367)

Merged via /review-pr -> /prepare-pr -> /merge-pr.

Prepared head SHA: bf02bbf9ce
Co-authored-by: Lukavyi <1013690+Lukavyi@users.noreply.github.com>
Co-authored-by: obviyus <22031114+obviyus@users.noreply.github.com>
Reviewed-by: @obviyus

src/infra/heartbeat-runner.returns-default-unset.test.ts

@@ -305,6 +305,46 @@ describe("resolveHeartbeatDeliveryTarget", () => {
     });
   });
 
+  it("keeps explicit telegram targets", () => {
+    const cfg: OpenClawConfig = {
+      agents: { defaults: { heartbeat: { target: "telegram", to: "123" } } },
+    };
+    expect(resolveHeartbeatDeliveryTarget({ cfg, entry: baseEntry })).toEqual({
+      channel: "telegram",
+      to: "123",
+      accountId: undefined,
+      lastChannel: undefined,
+      lastAccountId: undefined,
+    });
+  });
+
+  it("parses threadId from :topic: suffix in heartbeat to", () => {
+    const cfg: OpenClawConfig = {
+      agents: {
+        defaults: {
+          heartbeat: { target: "telegram", to: "-100111:topic:42" },
+        },
+      },
+    };
+    const result = resolveHeartbeatDeliveryTarget({ cfg, entry: baseEntry });
+    expect(result.channel).toBe("telegram");
+    expect(result.to).toBe("-100111");
+    expect(result.threadId).toBe(42);
+  });
+
+  it("heartbeat to without :topic: has no threadId", () => {
+    const cfg: OpenClawConfig = {
+      agents: {
+        defaults: {
+          heartbeat: { target: "telegram", to: "-100111" },
+        },
+      },
+    };
+    const result = resolveHeartbeatDeliveryTarget({ cfg, entry: baseEntry });
+    expect(result.to).toBe("-100111");
+    expect(result.threadId).toBeUndefined();
+  });
+
   it("uses explicit heartbeat accountId when provided", () => {
     const cfg: OpenClawConfig = {
       agents: {