Codex CLI themes are genuinely unusable

Codex CLI version:
0.105.0

Description:
The background key inside .tmTheme scope rules for markup.inserted, markup.deleted, and markup.changed is completely ignored. The diff view always renders with hardcoded bright red/green backgrounds regardless of what's defined in the custom theme file.

Impact:
Unusable for anyone with a custom terminal color scheme. The bright hardcoded backgrounds cause serious eye strain and make it impossible to read the highlighted code. My eyes are begging for mercy.