fix: harden routing/session isolation for followups and heartbeat

src/auto-reply/reply/reply-flow.test.ts

@@ -1046,6 +1046,51 @@ describe("followup queue collect routing", () => {
     expect(calls[0]?.prompt).toContain("[Queue overflow] Dropped 1 message due to cap.");
     expect(calls[0]?.prompt).toContain("- first");
   });
+
+  it("preserves routing metadata on overflow summary followups", async () => {
+    const key = `test-overflow-summary-routing-${Date.now()}`;
+    const calls: FollowupRun[] = [];
+    const done = createDeferred<void>();
+    const runFollowup = async (run: FollowupRun) => {
+      calls.push(run);
+      done.resolve();
+    };
+    const settings: QueueSettings = {
+      mode: "followup",
+      debounceMs: 0,
+      cap: 1,
+      dropPolicy: "summarize",
+    };
+
+    enqueueFollowupRun(
+      key,
+      createRun({
+        prompt: "first",
+        originatingChannel: "discord",
+        originatingTo: "channel:C1",
+        originatingThreadId: "1739142736.000100",
+      }),
+      settings,
+    );
+    enqueueFollowupRun(
+      key,
+      createRun({
+        prompt: "second",
+        originatingChannel: "discord",
+        originatingTo: "channel:C1",
+        originatingThreadId: "1739142736.000100",
+      }),
+      settings,
+    );
+
+    scheduleFollowupDrain(key, runFollowup);
+    await done.promise;
+
+    expect(calls[0]?.originatingChannel).toBe("discord");
+    expect(calls[0]?.originatingTo).toBe("channel:C1");
+    expect(calls[0]?.originatingThreadId).toBe("1739142736.000100");
+    expect(calls[0]?.prompt).toContain("[Queue overflow] Dropped 1 message due to cap.");
+  });
 });
 
 const emptyCfg = {} as OpenClawConfig;