fix(proxy): ensure the host field is correct when using proxy

[Archkon]

The host field should be set according target url not the proxy url

refer to https://www.rfc-editor.org/rfc/rfc9112#section-3.2.2

[yury-s]

Please start with opening an issue that describes the problem, so that we can evaluate it.

[yury-s]

Looks good, but please add a test for this. See e.g. 'should use env proxy with connectOverCDP discovery request' in tests/library/chromium/connect-over-cdp.spec.ts.

[Archkon]

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[github-actions]

Test results for "tests 1"

3 flaky

⚠️ [chromium-library] › library/popup.spec.ts:261 › should not throw when click closes popup `@chromium-ubuntu-22.04-node24`
⚠️ [chromium-library] › library/video.spec.ts:682 › screencast › should capture full viewport on hidpi `@chromium-ubuntu-22.04-node22`
⚠️ [firefox-page] › page/expect-timeout.spec.ts:114 › should not miss element that appears between retries before the deadline `@firefox-ubuntu-22.04-node20`

41774 passed, 850 skipped

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Merge workflow run.

[github-actions]

Test results for "MCP"

3 failed
❌ [chrome] › mcp/annotate.spec.ts:57 › should capture multiple screenshots in one annotation @mcp-windows-latest-chrome
❌ [chromium] › mcp/annotate.spec.ts:367 › should cancel browser_annotate when the MCP request is aborted @mcp-windows-latest-chromium
❌ [msedge] › mcp/annotate.spec.ts:137 › should abort MCP annotation when last screenshot is removed @mcp-windows-latest-msedge

7083 passed, 1104 skipped

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Merge workflow run.