Compact editor tab height: Search controls too tight

[chrmarti]

Testing #334475

"window.density.editorTabHeight": "compact" makes the search controls and separator stick together:

Version: 1.137.0-insider
Commit: 94b021b
Date: 2026-09-07T01:46:17Z
Electron: 42.10.0
ElectronBuildId: 15109253
Chromium: 148.0.7778.280
Node.js: 24.18.1
V8: 14.8.178.38-electron.0
@github/copilot: 1.0.84-canary.70.gdb75d0d.unsigned
@github/copilot-sdk: 1.0.13-preview.4
OS: Darwin arm64 25.6.0

[vs-code-engineering]

Sharing media and context from merged PR #334948 for verification:

Summary

• Keep the Agents window search header at its normal height and vertical padding when editor tabs use compact density. The search controls remain full height and should not touch the results separator.
• Add real SearchEditor fixtures for default and compact density in dark, light, and dark high-contrast themes.
• Leave default-density spacing unchanged.

Validation

• All six fixtures render and dispose without errors.
• All six fixtures have stable screenshots; compact and default screenshots match in each theme.
• Targeted ESLint, stylelint, editor diagnostics, and git diff --check pass.
• Measured compact header: 32px high, with 26px input controls and 2px vertical padding. The input-to-separator gap increases from 0.75px to 2.75px.

Before

Original report with window.density.editorTabHeight set to compact:

How to test

1. In the Agents window, set window.density.editorTabHeight to compact and open the Search editor.
2. Verify there is visible spacing above and below the search controls and before the results separator.
3. Switch to default tab density and verify search-control spacing is unchanged.
4. In Component Explorer, review sessions/searchEditor/{Default,Compact}/{Dark,Light,DarkHighContrast}.

After

Fresh capture of the real SearchEditor compact-density fixture from this branch. The controls retain their full height with visible vertical padding before the separator.

Source PR: #334948