fix: themes, ui, translation

[roguehashrate]

Changes

• Significantly improved Light Mode – it's now much more pleasant to use (but yes, it's still light mode... so maybe grab some shades)
• Removed the following themes: Ashen, Miasma, Earthsong, and Neon Night
• Added two new themes: Ayu and Sapphire
• Enhanced the following themes with better colors and tuning:
  • Dracula → more pink accents
  • Gruvbox → more orange tones
  • Kanagawa → powder red adjustments
  • Srcery → richer green tones
• Fixed the "Switch to Text" button so it properly respects the user's current theme
• Fixed missing translations on the Gallery Post screen (now fully translated in all supported languages)