Restore Blacksky branding and theming after upstream merge
Restore the pre-merge color scheme and theming system that was
overwritten during the upstream social-app merge. The upstream merge
replaced our custom createThemes() with the @bsky.app/alf package
version and stripped CSS variables from style.css.
Theming:
- Restore custom createThemes() in themes.ts with BRAND constants
(indigo #6060E9, lime #D2FC51, twilight #161E27, etc.)
- Restore colorGeneration.ts with HSL-based dim palette generation
- Restore CSS variables and theme--light/dark/dim classes in style.css
- Restore ProseMirror mention color to rgb(96, 96, 233)
HTML templates:
- Restore pre-merge flash-prevention CSS (simple background/color
with prefers-color-scheme media query, no inline CSS variables)
- Restore Blacksky SVG splash with currentColor fill and
transform-based centering
- Update preconnect to blacksky.community/go.blacksky.community
- Set mask-icon and theme-color to #6060E9
Branding:
- Change tagline to "Join the Cookout" in NavSignupCard
- Blacksky logo, splash screens, and footer links
- Update @atproto/api patch for v0.18.18
- Replace bsky.social references with blackskyweb.xyz
- Default avatar color #6060E9
- Blacksky constants (endpoints, feeds, DIDs)