docs(theme): update documentation and clean up deprecated color scheme definitions

Removed outdated compatibility aliases and deprecated methods from AppColorScheme,
and updated CLAUDE.md to reflect new theme system requirements with centralized
color management and no hard-coded values in UI components.

flutter_monisuo/lib/ui/pages/mine/components/profile_card.dart

@@ -1,7 +1,7 @@
 import 'package:flutter/material.dart';
-import 'package:google_fonts/google_fonts.dart';
 import 'package:lucide_icons_flutter/lucide_icons.dart';
 import '../../../../core/theme/app_spacing.dart';
+import '../../../../core/theme/app_theme.dart';
 import 'avatar_circle.dart';
 
 /// 用户资料卡片 - 头像 + 用户名 + 徽章 + chevron
@@ -42,11 +42,7 @@ class ProfileCard extends StatelessWidget {
               children: [
                 Text(
                   user?.username ?? '未登录',
-                  style: GoogleFonts.inter(
-                    fontSize: 16,
-                    fontWeight: FontWeight.w600,
-                    color: colorScheme.onSurface,
-                  ),
+                  style: AppTextStyles.headlineLarge(context),
                 ),
                 const SizedBox(height: 4),
                 Text(