[tommynok]

Pure OLED black is great for battery life, but for users with astigmatism, reduced contrast sensitivity, or when reading outdoors under bright sunlight, high-contrast light backgrounds cause significantly less eyestrain.

This PR adds an optional Light Theme with a focus on readability and accessibility:

1. Light Theme Option:

   • Toggled via a switch on the Info tab ("Light theme" / "Use a light background instead of OLED black"), saved in SharedPreferences.
   • Clean, high-contrast surface (#F4F4F6 background, #FFFFFF cards, #000000 text).
   • Dynamic system status bar and navigation bar icon color adaptation (Android 6.0+ / 8.0+).
   • Bottom navigation tab bar protected with a minimum font floor (10.5sp) to keep tabs legible across screen sizes.
   • Added Spanish translations to es.tsv.

2. Debloater Level Readability:

   • In light mode, pastel 400-range colors (#FFCA28, #FF8A65) fail WCAG AA contrast against white (dropping as low as 1.3:1).
   • Added LEVEL_COLORS_LIGHT with WCAG AA/AAA compliant tones (#1B5E20, #B25E00, #C2410C, #B71C1C).
   • Split Debloater row subtitles with SpannableStringBuilder: only the risk level tag is colored, while descriptive notes are rendered in crisp dark neutral text (#222222), greatly improving reading comfort.
   • Zero impact on dark mode: the original OLED theme is 100% untouched and byte-for-byte identical.

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