fix(test runner): compile jsx to a location-independent runtime import

[Yury Semikhatsky (yury-s)]

Summary

• Compile JSX to import bare @playwright/test/jsx-runtime (re-exported from playwright/jsx-runtime) instead of an absolute path, so cached transforms no longer embed the install location.
• Alternative to fix(test runner): include jsxImportSource in transform cache hash #42938.

Fixes #42934

[github-actions]

Test results for "tests 1"

5 flaky

⚠️ [chromium-library] › library/popup.spec.ts:260 › should not throw when click closes popup `@chromium-ubuntu-22.04-arm-node20`
⚠️ [chromium-library] › library/video.spec.ts:762 › screencast › should work with video+trace `@chromium-ubuntu-22.04-arm-node20`
⚠️ [chromium-library] › library/popup.spec.ts:260 › should not throw when click closes popup `@chromium-ubuntu-22.04-node20`
⚠️ [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`

52303 passed, 1243 skipped

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Merge workflow run.

[github-actions]

Test results for "MCP"

5 failed
❌ [firefox] › mcp/annotate.spec.ts:446 › should switch screencast to -s session on show --annotate @mcp-windows-latest-firefox
❌ [firefox] › mcp/cli-core.spec.ts:57 › click link @mcp-windows-latest-firefox
❌ [firefox] › mcp/cli-devtools.spec.ts:86 › request shows full request and response details @mcp-windows-latest-firefox
❌ [firefox] › mcp/cli-drag.spec.ts:19 › drag between elements @mcp-windows-latest-firefox
❌ [firefox] › mcp/cli-session.spec.ts:54 › idle timeout shuts the session down @mcp-windows-latest-firefox

8759 passed, 1480 skipped

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Merge workflow run.

[github-actions]

Hi, I'm the Playwright bot and I took a first look at the CI failures here.

🟢 All 5 failures look like pre-existing flakes

All five failures are in MCP tests on mcp-windows-latest-firefox. Each of those tests has failed before on main pushes or other PRs, and this PR only touches JSX compilation in the test runner.

Details

This PR changes configLoader.ts, the @playwright/test JSX runtime entry points, and the cache/loader test-runner specs. The MCP CLI and annotate flows don't go through any of that, and none of the failures reproduce on non-Windows bots. The numbers below come from the test-results DB, [firefox] project, Windows bots only. On non-Windows bots each of these tests passed in every one of ~500–1,400 runs.

Pre-existing flake / infra

• mcp/annotate.spec.ts:446 › should switch screencast to -s session on show --annotate: failed in 77 of 703 Windows runs (11%), including 39 main pushes and 37 other PRs.
• mcp/cli-session.spec.ts:54 › idle timeout shuts the session down: failed in 61 of 265 Windows runs (23%), including 21 pushes and 36 other PRs.
• mcp/cli-drag.spec.ts:19 › drag between elements: failed in 14 of 705 Windows runs, including 4 pushes and 10 other PRs.
• mcp/cli-core.spec.ts:57 › click link: failed in 12 of 705 Windows runs, including 7 pushes and 5 other PRs.
• mcp/cli-devtools.spec.ts:86 › request shows full request and response details: failed in 4 of 705 Windows runs, all on other PRs.

This PR's own runs weren't in the DB snapshot yet; the refresh step hit a GitHub API error. The verdict is based on each test's earlier history.

_{Triaged by the Playwright bot - agent run}