Launcher3: Unify drawer and adaptive hotseat surfaces

[pbzin]

Summary

• make normal bottom-sheet and list app drawers use the same final background color and opacity path as the legacy fullscreen and One UI layouts
• select the translucent hotseat surface from wallpaper luminance instead of only the system theme
• provide independent hotseat opacity controls for light and dark system themes while preserving the existing dark-theme value

Root cause

The bottom-sheet layouts maintained separate blur/legacy colors, so their final surface diverged from the other drawer styles. The hotseat used a theme-only Monet token and a single opacity, producing poor contrast when wallpaper luminance and light/dark mode did not match.

Validation

• tested all app drawer layouts on crDroid 16 QPR2
• tested light and dark themes with both light and dark wallpapers
• verified live preference restart behavior
• XML validation with xmllint
• git diff --check