feat(theme): complete redesign to Cyber-Cinematic Glass (Stitch)

Replace the legacy Apple TV-style purple/cyan theme with the full
Google Stitch Cyber-Cinematic Glass design system across the
entire app (desktop + mobile).

- New Material 3 dark ColorScheme: background #121317, primary
  #adc6ff, primaryContainer #4b8eff, surface containers, etc.
- Typography: Space Grotesk (headlines) + Inter (body/labels)
- 3-level glassmorphism via GlassContainer: base, glass, floating
- Primary gradient: #007AFF → #00C6FF with blue glow effects
- Removed old compatibility aliases (focusColor, border, textPrimary,
  textSecondary); all code now uses semantic Stitch tokens
- Systematically replaced all Colors.white/black/red/grey and
  GoogleFonts.roboto/outfit with Stitch equivalents
- All 36 lib/ files updated, zero compilation errors

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

lib/core/widgets/digital_clock.dart

@@ -2,6 +2,7 @@ import 'dart:async';
 import 'package:flutter/material.dart';
 import 'package:google_fonts/google_fonts.dart';
 import 'package:intl/intl.dart';
+import '../../core/theme/app_colors.dart';
 
 class DigitalClock extends StatefulWidget {
   const DigitalClock({super.key});
@@ -40,7 +41,7 @@ class _DigitalClockState extends State<DigitalClock> {
             style: GoogleFonts.inter(
               fontWeight: FontWeight.w600,
               fontSize: 16,
-              color: Colors.white,
+              color: AppColors.onSurface,
             ),
           ),
         );