chore(fetch): only preserve error code across serialization

[Dmitry Gozman (dgozman)]

Summary

• Follow-up to fix(fetch): preserve node error fields across serialization #42562 after the API review: serialized errors keep only code; errno, syscall, address, port and hostname are removed.

[github-actions]

Test results for "tests 1"

1 failed
❌ [playwright-test] › snapshot-path-template.spec.ts:50 › tokens should expand property @windows-latest-node22

7 flaky

⚠️ [installation tests] › connect-to-selenium.spec.ts:20 › connect to selenium `@package-installations-ubuntu-latest`
⚠️ [chromium-library] › library/video.spec.ts:762 › screencast › should work with video+trace `@frozen-time-library-chromium-linux`
⚠️ [chromium-library] › library/chromium/chromium.spec.ts:179 › serviceWorker(), and fromServiceWorker() work `@realtime-time-library-chromium-linux`
⚠️ [chromium-library] › library/chromium/chromium.spec.ts:179 › serviceWorker(), and fromServiceWorker() work `@chromium-ubuntu-22.04-node22`
⚠️ [firefox-library] › library/browsercontext-cookies-third-party.spec.ts:257 › third party 'Partitioned;' cookies `@firefox-ubuntu-22.04-node20`
⚠️ [firefox-library] › library/browsercontext-cookies-third-party.spec.ts:470 › top level 'Partitioned;' cookie and same origin iframe `@firefox-ubuntu-22.04-node20`
⚠️ [firefox-library] › library/browsercontext-reuse.spec.ts:200 › reuse connect › should not cache resources `@firefox-ubuntu-22.04-node20`

52569 passed, 1270 skipped

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Merge workflow run.

[github-actions]

Test results for "MCP"

3 failed
❌ [chrome] › mcp/annotate.spec.ts:291 › should enter annotate mode on fresh dashboard.tsx mount with -s --annotate @mcp-windows-latest-chrome
❌ [msedge] › mcp/annotate.spec.ts:386 › should cancel browser_annotate when the MCP request is aborted @mcp-windows-latest-msedge
❌ [msedge] › mcp/annotate.spec.ts:417 › should cancel browser_annotate when the MCP client disconnects @mcp-windows-latest-msedge

8934 passed, 1489 skipped

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Merge workflow run.