Say when a scheduled task is running

A run is detached — cron has no terminal, and the app fires it as a detached
exec — so triggering one and watching the log was indistinguishable from
triggering one that died. Worse, `claude -p` writes its answer in a single
burst at the end, so a healthy run shows nothing but its log header for as
long as it is thinking. The honest reading of the old UI was "it stalled".

triple-c-task-runner now publishes a state file per run (pid, start time, log
path) and removes it from an EXIT trap. flock remains what actually prevents
overlapping runs; this is purely observability, so every reader verifies the
pid rather than trusting the file — a container stopped mid-run cannot fire a
trap, and a task stuck on "running" forever would be a worse lie than no
indicator at all. Stale files are cleared on read.

On top of that:

- `list` grows a status column: "running 4m12s" or "idle".
- `status [--id] [--watch]` answers "is it still going?" directly, with
  elapsed time and the tail of the log when there is any output yet.
- `run` streams the log instead of blocking silently, and refuses to start a
  task that is already running.
- The Automation tab marks a running task, disables its Run now button, and
  polls while anything is in flight — including the second or two between
  firing a run and the runner registering it, which is the exact window that
  used to read as dead.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

app/src/components/projects/home/AutomationTab.test.tsx

@@ -0,0 +1,112 @@
+import { describe, it, expect, vi, beforeEach, afterEach } from "vitest";
+import { render, screen, fireEvent, act } from "@testing-library/react";
+import AutomationTab from "./AutomationTab";
+import type { Project, ScheduledTask } from "../../../lib/types";
+
+const listScheduledTasks = vi.fn(async () => tasks);
+const getSchedulerNotifications = vi.fn(async () => []);
+const runScheduledTaskNow = vi.fn(async () => "started");
+const pushToast = vi.fn();
+
+vi.mock("../../../lib/tauri-commands", () => ({
+  listScheduledTasks: () => listScheduledTasks(),
+  getSchedulerNotifications: () => getSchedulerNotifications(),
+  runScheduledTaskNow: (p: string, t: string) => runScheduledTaskNow(p, t),
+  clearSchedulerNotifications: vi.fn(async () => {}),
+  getScheduledTaskLog: vi.fn(async () => ""),
+  removeScheduledTask: vi.fn(async () => {}),
+  setScheduledTaskEnabled: vi.fn(async () => {}),
+}));
+
+vi.mock("../../../store/appState", () => ({
+  useAppState: (selector: (s: unknown) => unknown) => selector({ pushToast }),
+}));
+
+const project = { id: "p1", name: "api", status: "running" } as unknown as Project;
+
+const baseTask: ScheduledTask = {
+  id: "a1b2c3d4",
+  name: "nightly",
+  prompt: "Run the suite",
+  schedule: "0 3 * * *",
+  task_type: "recurring",
+  at: null,
+  enabled: true,
+  working_dir: "/workspace",
+  created_at: null,
+  last_run: null,
+  next_run: null,
+  running: false,
+  running_since: null,
+};
+
+let tasks: ScheduledTask[] = [];
+
+async function renderTab() {
+  render(<AutomationTab project={project} />);
+  await act(async () => {
+    await Promise.resolve();
+  });
+}
+
+beforeEach(() => {
+  vi.useFakeTimers({ shouldAdvanceTime: true });
+  tasks = [baseTask];
+  listScheduledTasks.mockClear();
+  runScheduledTaskNow.mockClear();
+});
+
+afterEach(() => {
+  vi.useRealTimers();
+});
+
+describe("AutomationTab run state", () => {
+  it("offers Run now for an idle task and says nothing about running", async () => {
+    await renderTab();
+    expect(screen.getByRole("button", { name: "Run now" })).toBeEnabled();
+    expect(screen.queryByText(/Running/)).toBeNull();
+  });
+
+  it("shows a running task as running, with elapsed time, and blocks a second trigger", async () => {
+    const startedSecondsAgo = new Date(Date.now() - 90_000).toISOString();
+    tasks = [{ ...baseTask, running: true, running_since: startedSecondsAgo }];
+    await renderTab();
+
+    // The whole point: a detached run is visible rather than silent.
+    expect(screen.getByText(/Running for 1m/)).toBeTruthy();
+    expect(screen.getByRole("button", { name: "Running…" })).toBeDisabled();
+  });
+
+  it("keeps polling after a trigger, so a run that has not registered yet still appears", async () => {
+    await renderTab();
+    const callsAfterLoad = listScheduledTasks.mock.calls.length;
+
+    // The runner needs a moment to write its state file; until then the task
+    // still reads as idle, which is exactly the window that used to look dead.
+    await act(async () => {
+      fireEvent.click(screen.getByRole("button", { name: "Run now" }));
+      await Promise.resolve();
+    });
+    expect(runScheduledTaskNow).toHaveBeenCalledWith("p1", "a1b2c3d4");
+
+    tasks = [{ ...baseTask, running: true, running_since: new Date().toISOString() }];
+    await act(async () => {
+      vi.advanceTimersByTime(2000);
+      await Promise.resolve();
+    });
+
+    expect(listScheduledTasks.mock.calls.length).toBeGreaterThan(callsAfterLoad);
+    expect(screen.getByRole("button", { name: "Running…" })).toBeDisabled();
+  });
+
+  it("stops polling once nothing is running", async () => {
+    await renderTab();
+    // No trigger, nothing running: the interval must not be armed at all.
+    const before = listScheduledTasks.mock.calls.length;
+    await act(async () => {
+      vi.advanceTimersByTime(30_000);
+      await Promise.resolve();
+    });
+    expect(listScheduledTasks.mock.calls.length).toBe(before);
+  });
+});