fix(esm): strip stylesheet imports

[rkdfx]

Summary

• Apply css-to-identity-obj-proxy in ESM as well as CJS so stylesheet imports are stripped before Node loads them.
• Extend regex to also cover .sass and .styl.

Fixes #39187

[rkdfx]

@microsoft-github-policy-service agree

[github-actions]

Test results for "MCP"

9 failed
❌ [chrome] › mcp/cli-config.spec.ts:80 › context options with UTF-8 BOM @mcp-macos-latest-chrome
❌ [firefox] › mcp/dashboard.spec.ts:232 › should annotate via direct browser_annotate MCP call @mcp-windows-latest-firefox
❌ [firefox] › mcp/dashboard.spec.ts:265 › should annotate when context has no fixed viewport @mcp-windows-latest-firefox
❌ [firefox] › mcp/dashboard.spec.ts:302 › should cancel browser_annotate when the MCP request is aborted @mcp-windows-latest-firefox
❌ [firefox] › mcp/dashboard.spec.ts:333 › should cancel browser_annotate when the MCP client disconnects @mcp-windows-latest-firefox
❌ [firefox] › mcp/dashboard.spec.ts:362 › should switch screencast to -s session on show --annotate @mcp-windows-latest-firefox
❌ [firefox] › mcp/dashboard.spec.ts:411 › should disengage annotate mode when --annotate client disconnects @mcp-windows-latest-firefox
❌ [firefox] › mcp/dashboard.spec.ts:478 › save recording streams WebM bytes to the chosen file @mcp-windows-latest-firefox
❌ [webkit] › mcp/dashboard.spec.ts:333 › should cancel browser_annotate when the MCP client disconnects @mcp-windows-latest-webkit

6867 passed, 1015 skipped

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Merge workflow run.

[github-actions]

Test results for "tests 1"

6 flaky

⚠️ [chromium-library] › library/video.spec.ts:682 › screencast › should capture full viewport on hidpi `@chromium-ubuntu-22.04-arm-node20`
⚠️ [chromium-library] › library/video.spec.ts:719 › screencast › should work with video+trace `@chromium-ubuntu-22.04-node24`
⚠️ [chromium-library] › library/beforeunload.spec.ts:130 › should support dismissing the dialog multiple times `@chromium-ubuntu-22.04-node20`
⚠️ [chromium-library] › library/video.spec.ts:275 › screencast › should capture navigation `@chromium-ubuntu-22.04-node20`
⚠️ [chromium-library] › library/video.spec.ts:647 › screencast › should capture full viewport `@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`

41648 passed, 784 skipped

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Merge workflow run.

[pavelfeldman]

We don't quite expect these in our e2e test sources.

[rkdfx]

Did you mean the failing tests? It seems these are failing on main as well (tried locally).