fix: reschedule heartbeat on hot reload

Co-authored-by: Seb Slight <sebslight@users.noreply.github.com>

src/infra/heartbeat-runner.scheduler.test.ts

@@ -0,0 +1,57 @@
+import { afterEach, describe, expect, it, vi } from "vitest";
+import type { ClawdbotConfig } from "../config/config.js";
+import { startHeartbeatRunner } from "./heartbeat-runner.js";
+
+describe("startHeartbeatRunner", () => {
+  afterEach(() => {
+    vi.useRealTimers();
+    vi.restoreAllMocks();
+  });
+
+  it("updates scheduling when config changes without restart", async () => {
+    vi.useFakeTimers();
+    vi.setSystemTime(new Date(0));
+
+    const runSpy = vi.fn().mockResolvedValue({ status: "ran", durationMs: 1 });
+
+    const runner = startHeartbeatRunner({
+      cfg: {
+        agents: { defaults: { heartbeat: { every: "30m" } } },
+      } as ClawdbotConfig,
+      runOnce: runSpy,
+    });
+
+    await vi.advanceTimersByTimeAsync(30 * 60_000 + 1_000);
+
+    expect(runSpy).toHaveBeenCalledTimes(1);
+    expect(runSpy.mock.calls[0]?.[0]).toEqual(
+      expect.objectContaining({ agentId: "main", reason: "interval" }),
+    );
+
+    runner.updateConfig({
+      agents: {
+        defaults: { heartbeat: { every: "30m" } },
+        list: [
+          { id: "main", heartbeat: { every: "10m" } },
+          { id: "ops", heartbeat: { every: "15m" } },
+        ],
+      },
+    } as ClawdbotConfig);
+
+    await vi.advanceTimersByTimeAsync(10 * 60_000 + 1_000);
+
+    expect(runSpy).toHaveBeenCalledTimes(2);
+    expect(runSpy.mock.calls[1]?.[0]).toEqual(
+      expect.objectContaining({ agentId: "main", heartbeat: { every: "10m" } }),
+    );
+
+    await vi.advanceTimersByTimeAsync(5 * 60_000 + 1_000);
+
+    expect(runSpy).toHaveBeenCalledTimes(3);
+    expect(runSpy.mock.calls[2]?.[0]).toEqual(
+      expect.objectContaining({ agentId: "ops", heartbeat: { every: "15m" } }),
+    );
+
+    runner.stop();
+  });
+});