Yazi's newer TOML parser requires kebab-case key names.
$schema starts with a non-letter character, causing:
TOML parse error at line 3: must be a kebab-cased string
Add source = mocha.conf before pywal's colors-hyprland.conf so
Catppuccin Mocha colors always load as defaults. Also define
$color1, $color2, $color3, and $background in mocha.conf as
fallbacks for when pywal hasn't generated its color file.
Fixes two Hyprland errors:
- 'source= globbing error: found no match' when pywal file missing
- 'failed to parse $color2 as a color' gradient parsing error
