fix(cli-provider): add timeout protection for external CLI processes

Prevent builds from hanging indefinitely when CLI provider subprocess
is unresponsive. Default 2h for runTaskInWorkflow, 1h for watchWorkflow.
Graceful SIGTERM with 10s grace before SIGKILL.

- Added RUN_TASK_TIMEOUT_MS (2 hours) and WATCH_WORKFLOW_TIMEOUT_MS (1 hour)
- Added gracefulKill helper: SIGTERM first, SIGKILL after 10s grace period
- runTaskInWorkflow and watchWorkflow now have timeout protection
- Existing execute() method upgraded to use gracefulKill
- core.error() called with clear human-readable timeout message
- Added comprehensive tests: timeout triggers, SIGKILL escalation,
  grace period cancellation on voluntary exit, normal completion

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/model/orchestrator/providers/cli/cli-provider.test.ts

@@ -20,6 +20,7 @@ jest.mock('@actions/core', () => ({
 jest.mock('../provider-git-manager');
 
 import { spawn } from 'child_process';
+import * as core from '@actions/core';
 import CliProvider from './cli-provider';
 
 const mockSpawn = spawn as jest.MockedFunction<typeof spawn>;
@@ -215,6 +216,18 @@ describe('CliProvider', () => {
       const result = await promise;
       expect(result).toBe('line 1\nline 2');
     });
+
+    it('rejects on spawn error', async () => {
+      const child = createMockChildProcess();
+      mockSpawn.mockReturnValue(child);
+
+      const provider = new CliProvider('/nonexistent/path', {} as any);
+      const promise = provider.runTaskInWorkflow('guid', 'image', 'cmd', '/mnt', '/work', [], []);
+
+      child.emit('error', new Error('ENOENT'));
+
+      await expect(promise).rejects.toThrow('failed to spawn executable');
+    });
   });
 
   describe('cleanupWorkflow', () => {
@@ -404,7 +417,7 @@ describe('CliProvider', () => {
       jest.useRealTimers();
     });
 
-    it('rejects and kills process when command times out', async () => {
+    it('rejects and kills process when execute command times out', async () => {
       const child = createMockChildProcess();
       mockSpawn.mockReturnValue(child);
 
@@ -417,6 +430,97 @@ describe('CliProvider', () => {
       await expect(promise).rejects.toThrow('timed out');
       expect(child.kill).toHaveBeenCalledWith('SIGTERM');
     });
+
+    it('rejects and kills process when runTaskInWorkflow times out', async () => {
+      const child = createMockChildProcess();
+      mockSpawn.mockReturnValue(child);
+
+      const provider = new CliProvider('/path/to/exe', {} as any);
+      const promise = provider.runTaskInWorkflow('guid', 'image', 'cmd', '/mnt', '/work', [], []);
+
+      // Advance past the 2-hour timeout (7_200_000ms)
+      jest.advanceTimersByTime(7_200_001);
+
+      await expect(promise).rejects.toThrow('run-task timed out');
+      expect(child.kill).toHaveBeenCalledWith('SIGTERM');
+      expect(core.error).toHaveBeenCalledWith(expect.stringContaining('CLI provider timed out after 120 minutes'));
+    });
+
+    it('rejects and kills process when watchWorkflow times out', async () => {
+      const child = createMockChildProcess();
+      mockSpawn.mockReturnValue(child);
+
+      const provider = new CliProvider('/path/to/exe', {} as any);
+      const promise = provider.watchWorkflow();
+
+      // Advance past the 1-hour timeout (3_600_000ms)
+      jest.advanceTimersByTime(3_600_001);
+
+      await expect(promise).rejects.toThrow('watch-workflow timed out');
+      expect(child.kill).toHaveBeenCalledWith('SIGTERM');
+      expect(core.error).toHaveBeenCalledWith(expect.stringContaining('CLI provider timed out after 60 minutes'));
+    });
+
+    it('escalates to SIGKILL after grace period on runTaskInWorkflow timeout', async () => {
+      const child = createMockChildProcess();
+      mockSpawn.mockReturnValue(child);
+
+      const provider = new CliProvider('/path/to/exe', {} as any);
+      const promise = provider.runTaskInWorkflow('guid', 'image', 'cmd', '/mnt', '/work', [], []);
+
+      // Trigger the timeout
+      jest.advanceTimersByTime(7_200_001);
+
+      await expect(promise).rejects.toThrow('timed out');
+
+      // SIGTERM was sent
+      expect(child.kill).toHaveBeenCalledWith('SIGTERM');
+
+      // Advance past the 10s grace period — SIGKILL should fire
+      jest.advanceTimersByTime(10_001);
+      expect(child.kill).toHaveBeenCalledWith('SIGKILL');
+    });
+
+    it('does not send SIGKILL if process exits before grace period', async () => {
+      const child = createMockChildProcess();
+      mockSpawn.mockReturnValue(child);
+
+      const provider = new CliProvider('/path/to/exe', {} as any);
+      const promise = provider.runTaskInWorkflow('guid', 'image', 'cmd', '/mnt', '/work', [], []);
+
+      // Trigger the timeout
+      jest.advanceTimersByTime(7_200_001);
+
+      await expect(promise).rejects.toThrow('timed out');
+
+      // Process exits voluntarily after SIGTERM
+      child.emit('close', 143);
+
+      // Advance past the grace period — SIGKILL should NOT fire because process already exited
+      jest.advanceTimersByTime(10_001);
+      expect(child.kill).toHaveBeenCalledWith('SIGTERM');
+      // SIGKILL should not have been called because the close event cleared the timer
+      expect(child.kill).not.toHaveBeenCalledWith('SIGKILL');
+    });
+
+    it('clears timeout when runTaskInWorkflow completes normally', async () => {
+      const child = createMockChildProcess();
+      mockSpawn.mockReturnValue(child);
+
+      const provider = new CliProvider('/path/to/exe', {} as any);
+      const promise = provider.runTaskInWorkflow('guid', 'image', 'cmd', '/mnt', '/work', [], []);
+
+      // Process completes before timeout
+      child.stdout.emit('data', Buffer.from(JSON.stringify({ success: true, output: 'done' }) + '\n'));
+      child.emit('close', 0);
+
+      const result = await promise;
+      expect(result).toBe('done');
+
+      // Advance far past timeout — should NOT reject
+      jest.advanceTimersByTime(8_000_000);
+      expect(child.kill).not.toHaveBeenCalled();
+    });
   });
 
   describe('available providers list', () => {