fix(trace-viewer): prevent browser address bar bouncing based on URL

[agg23]

The Trace Viewer browser snapshot view has an address bar that was varying in height based on the URL present in it. Make the height uniform, and properly vertically center the traffic lights that were positioned by hand previously.

After

Before

[github-actions]

Test results for "tests 1"

3 flaky

⚠️ [firefox-library] › library/inspector/cli-codegen-1.spec.ts:1079 › cli codegen › should not throw csp directive violation errors `@firefox-ubuntu-22.04-node18`
⚠️ [firefox-page] › page/page-event-request.spec.ts:182 › should return response body when Cross-Origin-Opener-Policy is set `@firefox-ubuntu-22.04-node18`
⚠️ [playwright-test] › ui-mode-trace.spec.ts:397 › should work behind reverse proxy `@macos-latest-node18-1`

46775 passed, 821 skipped

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Merge workflow run.