- Inject ThemePreferences into MainActivity and apply dynamic theme selection
- Replace all hardcoded color references (DeepNavy, DarkNavy, CyanPrimary, TextPrimary, etc.) with MaterialTheme.colorScheme equivalents throughout AddLinkScreen and LoginScreen
- Update component colors to use Material3 color roles (primary, onBackground, surfaceVariant, outline, etc.)
- Migrate GlassCard, buttons, text fields, switches, and progress