* fix: add bg/fg aliases for theme color resolution
Themes define bg/fg but the template system expects
background/foreground. The fallback chain only checked color0/color7,
leaving background/foreground empty for themes using bg/fg naming.
* Complete legacy theme palette compatibility
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Co-authored-by: David Heinemeier Hansson <david@hey.com>
The canonical colors.toml keys are now background/foreground, including
all permutations (dark_background, darker_background, lighter_background,
dark_foreground, light_foreground, bright_foreground). The old short
names are gone entirely, not kept as aliases; legacy alacritty-generated
themes still resolve through the ANSI color0/color7 fallback.
Theme files are also regrouped: accent/selection/muted first, then the
backgrounds, then the foregrounds, then the named colors.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
