feat: support multiple HTTP credentials

[dgozman]

Summary

• httpCredentials option now also accepts an array of credentials, in browser.newContext(), request.newContext() and other places.
• The first entry matching the request origin is used, entries without an origin match any request.
• Requires the rolled Firefox r1539 / WebKit r2337 for multiple credentials in those browsers.

Fixes #22013

[github-actions]

Test results for "tests 1"

3 flaky

⚠️ [chromium-library] › library/video.spec.ts:495 › screencast › should capture static page in persistent context @smoke `@frozen-time-library-chromium-linux`
⚠️ [chromium-library] › library/video.spec.ts:736 › screencast › should work with video+trace `@chromium-ubuntu-22.04-node24`
⚠️ [chromium-library] › library/video.spec.ts:495 › screencast › should capture static page in persistent context @smoke `@chromium-ubuntu-22.04-node22`

50660 passed, 1190 skipped

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Merge workflow run.

[github-actions]

Test results for "MCP"

1 failed
❌ [firefox] › mcp/cli-core.spec.ts:189 › dialog-accept @mcp-windows-latest-firefox

7794 passed, 1266 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.

🟢 CI is clear — the one failure is a pre-existing flake

[firefox] › mcp/cli-core.spec.ts:189 › dialog-accept <prompt> fails on mcp-windows-latest-firefox, and it's been failing on main and unrelated PRs too — nothing to do with the HTTP credentials change here.

Details

This PR adds array support to httpCredentials across the client, fetch, and the per-browser network managers. Nothing it touches goes near the MCP CLI dialog flow. Two reports came back:

• tests 1 — 3 flaky, 0 failures (all library/video.spec.ts screencast). Flaky only, nothing to triage.
• MCP — 1 failure: [firefox] › mcp/cli-core.spec.ts:189 › dialog-accept <prompt> on mcp-windows-latest-firefox.

Pre-existing flake / infra

• [firefox] › mcp/cli-core.spec.ts:189 › dialog-accept <prompt> — pre-existing flake on mcp-windows-latest-firefox. In the test-results DB it failed 6 of 1123 firefox runs and passed the other 1117; it's 0/1147 on chromium, 0/1155 on webkit, 0/260 on msedge — Firefox-Windows only. Those 6 failures span runs this PR can't be responsible for: main (sha dba907bd), PR feat(test-runner): support named test locks #41862, PR feat(webkit): roll to r2337 #41971 (twice), PR Revert "chore(deps-dev): bump fast-uri from 3.1.3 to 3.1.4" #41978, and this PR once. Same test, same bot, unrelated SHAs → flake, not caused by this change.

_{Triaged by the Playwright bot - agent run}