fix(desktop): align macOS traffic lights with toolbar icons

[kev1n77]

Summary

Adjust the macOS native traffic-light vertical position from 15 to 22.5 logical pixels to align with the 45px toolbar row.

Related issue: N/A.

Type and Areas

Type: Bug fix / UI/UX

Areas: Desktop / Tauri (macOS)

Motivation / Impact

The native close, minimize, and fullscreen buttons appear above the other toolbar icons on macOS. Move them down by 7.5 logical pixels while preserving their horizontal spacing.

Verification

• pnpm run fmt:rs — passed.
• git diff --check — passed.
• cargo check -p openbitfun-desktop --offline — passed on Windows.
• pnpm --dir src/web-ui exec vitest run src/app/layout/WorkspaceBody.presentation.test.ts — 4 tests passed.
• The standard test script was blocked during its design-system prebuild by a missing @openbitfun/token-engine workspace dependency; the focused tests passed when invoked directly.
• macOS visual verification remains pending. Windows checks do not validate native macOS button placement.
• Remote workspace, remote control, Peer Device Mode, and Detached Dispatch were not exercised.

Reviewer Notes

• AI-assisted; lightly tested.
• The change is limited to the macOS native window creation configuration.
• Rebuild and restart on macOS to verify alignment with both expanded and collapsed sidebars. Frontend hot reload does not apply this change.
• No persisted data, protocols, or user-facing strings changed.

Checklist

• This PR is focused and does not include secrets, temporary prompts, generated scratch files, or unrelated artifacts.
• Relevant verification is recorded above, or skipped checks are explained.
• User-facing strings, docs, and locales are updated where applicable.