feat: add Chrome DevTools Protocol browser tools

Add BrowserManager (puppeteer-core) with page pool and auto-detection of
Chrome/Chromium. Six tools: browser.navigate, browser.screenshot,
browser.click, browser.type, browser.content, browser.eval. Feature is
opt-in (browser.enabled defaults to false). Add to coding tool profile.
Includes 22 unit tests for manager and all tools.

src/tools/builtin/browser/tools.test.ts

@@ -0,0 +1,157 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest';
+import { createBrowserTools } from './tools.js';
+import type { BrowserManager } from './manager.js';
+
+const mockGoto = vi.fn().mockResolvedValue(undefined);
+const mockTitle = vi.fn().mockResolvedValue('Test Page');
+const mockUrl = vi.fn().mockReturnValue('https://example.com');
+const mockClick = vi.fn().mockResolvedValue(undefined);
+const mockType = vi.fn().mockResolvedValue(undefined);
+const mock$eval = vi.fn().mockResolvedValue('Page content here');
+const mockEvaluate = vi.fn().mockResolvedValue({ result: 42 });
+const mockScreenshot = vi.fn().mockResolvedValue('base64data');
+const mock$ = vi.fn().mockResolvedValue({ screenshot: vi.fn().mockResolvedValue('element-base64') });
+const mockKeyboard = { press: vi.fn().mockResolvedValue(undefined) };
+
+const mockPage = {
+  goto: mockGoto,
+  title: mockTitle,
+  url: mockUrl,
+  click: mockClick,
+  type: mockType,
+  $eval: mock$eval,
+  evaluate: mockEvaluate,
+  screenshot: mockScreenshot,
+  $: mock$,
+  keyboard: mockKeyboard,
+  isClosed: () => false,
+};
+
+const mockManager = {
+  getPage: vi.fn().mockResolvedValue(mockPage),
+} as unknown as BrowserManager;
+
+describe('Browser tools', () => {
+  let tools: ReturnType<typeof createBrowserTools>;
+
+  beforeEach(() => {
+    vi.clearAllMocks();
+    tools = createBrowserTools(mockManager);
+  });
+
+  it('creates all browser tools', () => {
+    const names = tools.map(t => t.name);
+    expect(names).toContain('browser.navigate');
+    expect(names).toContain('browser.screenshot');
+    expect(names).toContain('browser.click');
+    expect(names).toContain('browser.type');
+    expect(names).toContain('browser.content');
+    expect(names).toContain('browser.eval');
+    expect(names).toHaveLength(6);
+  });
+
+  it('browser.navigate navigates to URL', async () => {
+    const tool = tools.find(t => t.name === 'browser.navigate')!;
+    const result = await tool.execute({ url: 'https://example.com' });
+    expect(result.success).toBe(true);
+    expect(result.output).toContain('example.com');
+    expect(mockGoto).toHaveBeenCalledWith('https://example.com', { waitUntil: 'domcontentloaded' });
+  });
+
+  it('browser.navigate respects custom waitUntil', async () => {
+    const tool = tools.find(t => t.name === 'browser.navigate')!;
+    await tool.execute({ url: 'https://example.com', waitUntil: 'networkidle0' });
+    expect(mockGoto).toHaveBeenCalledWith('https://example.com', { waitUntil: 'networkidle0' });
+  });
+
+  it('browser.screenshot takes page screenshot', async () => {
+    const tool = tools.find(t => t.name === 'browser.screenshot')!;
+    const result = await tool.execute({});
+    expect(result.success).toBe(true);
+    expect(result.output).toContain('Screenshot captured');
+    expect(mockScreenshot).toHaveBeenCalledWith({ encoding: 'base64', fullPage: false });
+  });
+
+  it('browser.screenshot takes element screenshot', async () => {
+    const tool = tools.find(t => t.name === 'browser.screenshot')!;
+    const result = await tool.execute({ selector: '#header' });
+    expect(result.success).toBe(true);
+    expect(mock$).toHaveBeenCalledWith('#header');
+  });
+
+  it('browser.screenshot fails for missing element', async () => {
+    mock$.mockResolvedValueOnce(null);
+    const tool = tools.find(t => t.name === 'browser.screenshot')!;
+    const result = await tool.execute({ selector: '#nonexistent' });
+    expect(result.success).toBe(false);
+    expect(result.error).toContain('Element not found');
+  });
+
+  it('browser.click clicks element', async () => {
+    const tool = tools.find(t => t.name === 'browser.click')!;
+    const result = await tool.execute({ selector: '#submit' });
+    expect(result.success).toBe(true);
+    expect(mockClick).toHaveBeenCalledWith('#submit');
+  });
+
+  it('browser.type types into element', async () => {
+    const tool = tools.find(t => t.name === 'browser.type')!;
+    const result = await tool.execute({ selector: '#search', text: 'hello' });
+    expect(result.success).toBe(true);
+    expect(mockType).toHaveBeenCalledWith('#search', 'hello');
+  });
+
+  it('browser.type clears field before typing when clear=true', async () => {
+    const tool = tools.find(t => t.name === 'browser.type')!;
+    await tool.execute({ selector: '#search', text: 'hello', clear: true });
+    expect(mockClick).toHaveBeenCalledWith('#search', { count: 3 });
+    expect(mockKeyboard.press).toHaveBeenCalledWith('Backspace');
+    expect(mockType).toHaveBeenCalledWith('#search', 'hello');
+  });
+
+  it('browser.content returns page text', async () => {
+    const tool = tools.find(t => t.name === 'browser.content')!;
+    const result = await tool.execute({});
+    expect(result.success).toBe(true);
+    expect(result.output).toContain('Page content here');
+    expect(result.output).toContain('example.com');
+    expect(result.output).toContain('Test Page');
+  });
+
+  it('browser.content uses custom selector', async () => {
+    const tool = tools.find(t => t.name === 'browser.content')!;
+    await tool.execute({ selector: '#main' });
+    expect(mock$eval).toHaveBeenCalledWith('#main', expect.any(Function));
+  });
+
+  it('browser.eval evaluates JS', async () => {
+    const tool = tools.find(t => t.name === 'browser.eval')!;
+    const result = await tool.execute({ expression: '1 + 1' });
+    expect(result.success).toBe(true);
+    expect(result.output).toContain('42');
+  });
+
+  it('browser.eval returns string results directly', async () => {
+    mockEvaluate.mockResolvedValueOnce('hello world');
+    const tool = tools.find(t => t.name === 'browser.eval')!;
+    const result = await tool.execute({ expression: '"hello world"' });
+    expect(result.success).toBe(true);
+    expect(result.output).toBe('hello world');
+  });
+
+  it('handles navigation errors gracefully', async () => {
+    mockGoto.mockRejectedValueOnce(new Error('Navigation failed'));
+    const tool = tools.find(t => t.name === 'browser.navigate')!;
+    const result = await tool.execute({ url: 'https://broken.example.com' });
+    expect(result.success).toBe(false);
+    expect(result.error).toContain('Navigation failed');
+  });
+
+  it('handles click errors gracefully', async () => {
+    mockClick.mockRejectedValueOnce(new Error('Element not found'));
+    const tool = tools.find(t => t.name === 'browser.click')!;
+    const result = await tool.execute({ selector: '#missing' });
+    expect(result.success).toBe(false);
+    expect(result.error).toContain('Element not found');
+  });
+});