fix(server): close browsers when PlaywrightServer shuts down

[pavelfeldman]

Summary

• In extension/reuse mode, PlaywrightServer launches browsers that intentionally outlive individual client connections (for reuse across reconnects). However, when the server itself shuts down via close(), those browsers were never cleaned up — leaking browser processes.
• This caused consistent worker teardown timeouts (30s) for debug-controller.spec.ts on all three Edge/macOS CI bots. The orphaned Edge process kept SmartScreen background connections alive, preventing clean shutdown of worker-scoped test fixtures.
• Fix: after closing the WebSocket server (which runs per-connection dispose callbacks), close any browsers still owned by the server's Playwright instance.

[github-actions]

Test results for "MCP"

14 failed
❌ [chrome] › mcp/dashboard.spec.ts:135 › should capture annotations via show --annotate @mcp-windows-latest
❌ [chrome] › mcp/dashboard.spec.ts:156 › should start dashboard and annotate when no dashboard is running @mcp-windows-latest
❌ [chromium] › mcp/dashboard.spec.ts:135 › should capture annotations via show --annotate @mcp-windows-latest
❌ [chromium] › mcp/dashboard.spec.ts:156 › should start dashboard and annotate when no dashboard is running @mcp-windows-latest
❌ [firefox] › mcp/cli-devtools.spec.ts:141 › video-start-stop @mcp-windows-latest
❌ [firefox] › mcp/cli-devtools.spec.ts:155 › video-chapter @mcp-windows-latest
❌ [firefox] › mcp/cli-session.spec.ts:50 › close @mcp-windows-latest
❌ [firefox] › mcp/cli-session.spec.ts:85 › close-all @mcp-windows-latest
❌ [firefox] › mcp/dashboard.spec.ts:135 › should capture annotations via show --annotate @mcp-windows-latest
❌ [firefox] › mcp/dashboard.spec.ts:156 › should start dashboard and annotate when no dashboard is running @mcp-windows-latest
❌ [webkit] › mcp/dashboard.spec.ts:135 › should capture annotations via show --annotate @mcp-windows-latest
❌ [webkit] › mcp/dashboard.spec.ts:156 › should start dashboard and annotate when no dashboard is running @mcp-windows-latest
❌ [msedge] › mcp/dashboard.spec.ts:135 › should capture annotations via show --annotate @mcp-windows-latest
❌ [msedge] › mcp/dashboard.spec.ts:156 › should start dashboard and annotate when no dashboard is running @mcp-windows-latest

6407 passed, 976 skipped

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Merge workflow run.

[github-actions]

Test results for "tests 1"

1 failed
❌ [installation tests] › playwright-electron-should-work.spec.ts:21 › electron should work @package-installations-ubuntu-latest

5 flaky

⚠️ [installation tests] › playwright-electron-should-work.spec.ts:31 › electron should work with special characters in path `@package-installations-ubuntu-latest`
⚠️ [chromium-library] › library/video.spec.ts:719 › screencast › should work with video+trace `@ubuntu-22.04-chromium-tip-of-tree`
⚠️ [chromium-library] › library/video.spec.ts:476 › screencast › should capture static page in persistent context @smoke `@chromium-ubuntu-22.04-node20`
⚠️ [firefox-library] › library/inspector/cli-codegen-1.spec.ts:1080 › cli codegen › should not throw csp directive violation errors `@firefox-ubuntu-22.04-node20`
⚠️ [firefox-page] › page/page-emulate-media.spec.ts:144 › should keep reduced motion and color emulation after reload `@firefox-ubuntu-22.04-node20`

39242 passed, 847 skipped

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Merge workflow run.