Changed drawer backgroundColor from var(--mui-palette-background-default)
to var(--mui-palette-background-paper) to match Headlamp's standard drawer
and dialog style with proper opaque elevated surface.
Generated with [Claude Code](https://claude.ai/code)
via [Happy](https://happy.engineering)
Co-Authored-By: Claude <noreply@anthropic.com>
Co-Authored-By: Happy <yesreply@happy.engineering>