0ee4c81ac0
Closes #899. Detects light terminal profiles from COLORFGBG, keeps the existing dark theme as the fallback, and maps DeepSeek dark-palette cells to readable light surfaces in the existing ColorCompatBackend. Local verification: - cargo fmt --all -- --check - cargo test -p deepseek-tui palette --all-features - cargo test -p deepseek-tui color_compat --all-features - cargo build CI: all required checks passed on #931.