feat(tracing): add resourcesDir option to Tracing.startHar

[dgozman]

Summary

• Add resourcesDir option to Tracing.startHar to redirect attached response bodies to a user-chosen directory; defaults to the HAR file's directory. Throws when combined with a .zip HAR path.
• Refactor HAR export to a mode-based protocol (entries/archive), mirroring tracing.stopChunk so resources can be written directly to user paths in-process and the existing harUnzip flow is used remotely.
• Switch HarRecorder to SerializedFS.

[github-actions]

Test results for "tests 1"

4 flaky

⚠️ [chromium-library] › library/video.spec.ts:719 › screencast › should work with video+trace `@chromium-ubuntu-22.04-node24`
⚠️ [chromium-library] › library/video.spec.ts:275 › screencast › should capture navigation `@chromium-ubuntu-22.04-node22`
⚠️ [firefox-library] › library/inspector/cli-codegen-1.spec.ts:1080 › cli codegen › should not throw csp directive violation errors `@firefox-ubuntu-22.04-node20`
⚠️ [webkit-library] › library/video.spec.ts:275 › screencast › should capture navigation `@webkit-ubuntu-22.04-node20`

41489 passed, 847 skipped

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Merge workflow run.

[github-actions]

Test results for "MCP"

7 failed
❌ [firefox] › mcp/cli-core.spec.ts:31 › close @mcp-windows-latest
❌ [firefox] › mcp/cli-devtools.spec.ts:217 › video-start-stop @mcp-windows-latest
❌ [firefox] › mcp/cli-devtools.spec.ts:231 › video-chapter @mcp-windows-latest
❌ [firefox] › mcp/cli-session.spec.ts:86 › delete-data @mcp-windows-latest
❌ [msedge] › mcp/dashboard.spec.ts:207 › should enter annotate mode on fresh dashboard.tsx mount with -s --annotate @mcp-windows-latest
❌ [msedge] › mcp/dashboard.spec.ts:231 › should switch screencast to -s session on show --annotate @mcp-windows-latest
❌ [webkit] › mcp/dashboard.spec.ts:185 › should start dashboard and annotate when no dashboard is running @mcp-macos-latest

6814 passed, 927 skipped

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Merge workflow run.