fix(route): do not drop requests matching case-insensitive URLPattern

[Yury Semikhatsky (yury-s)]

Summary

• URLPattern doesn't expose ignoreCase, so the server rebuilt patterns as case-sensitive and skipped routing for matching requests.
• The server now always matches case-insensitively. This is a safe superset, and the client filters again with the original pattern.

Fixes #42918

[github-actions]

Test results for "tests 1"

5 flaky

⚠️ [chromium-library] › library/screencast.spec.ts:28 › screencast.start delivers frames via onFrame callback `@frozen-time-library-chromium-linux`
⚠️ [chromium-library] › library/browsercontext-page-event.spec.ts:160 › should work with Shift-clicking `@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`
⚠️ [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`

52295 passed, 1255 skipped

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Merge workflow run.

[github-actions]

Test results for "MCP"

2 failed
❌ [firefox] › mcp/sse.spec.ts:196 › sse transport browser lifecycle (persistent) @mcp-ubuntu-latest-firefox
❌ [firefox] › mcp/cli-core.spec.ts:123 › select @mcp-windows-latest-firefox

8736 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.

🟢 Both failures are pre-existing flakes

The two Firefox MCP failures have failed the same way on other PRs and on main pushes, and this PR only touches route URL matching (packages/isomorphic/urlMatch.ts), which neither test exercises.

Details

The "tests 1" report has only flaky tests, no failures. The only hard failures are the two in the "MCP" report. Neither test uses page.route or URL patterns, so the diff doesn't reach them.

Pre-existing flake / infra

• [firefox] › mcp/sse.spec.ts:196 › sse transport browser lifecycle (persistent) (mcp-ubuntu-latest-firefox). It failed with the same toEqual deep-equality diff on fix(html reporter): print show-report path relative to npm invocation dir #42897, on feat(reporter): and printOnlyFailures and --reporter-only-failures #42766, and on a push run with no PR (36037100925). Retries rescued it in 3 other runs. It passed in the rest of its 729 runs in the test-results DB.
• [firefox] › mcp/cli-core.spec.ts:123 › select (mcp-windows-latest-firefox). It failed with the same Expected substring: "- option \"Two\" [selected]" error on feat(ui-mode): update individual snapshots #42421, on feat(cli): shut idle headless sessions down after an hour #42676, and on a push run (33913247836). Retries rescued it in 2 other runs. It's specific to Windows + Firefox.

_{Triaged by the Playwright bot - agent run}