feat(branding): 全平台品牌Logo替换 — 新双色渐变券印标识

## 概述
将全平台（5个前端应用）的品牌Logo从旧版钻石图标统一替换为新设计的
双色渐变券印标识（紫色#9B5CF6 + 品红#D946EF），体现券金融平台定位。

## 新Logo资源
- logo/genex-icon.svg: 纯图标（72x72），用于App图标和favicon
- logo/genex-04.svg: 带品牌名（380x72），用于启动画面和品牌展示

## 替换范围

### Flutter Apps（genex-mobile / admin-app / mobile）
- Android: 5个密度mipmap ic_launcher.png (48~192px)
- iOS: 15个AppIcon尺寸 (20~1024px) + 3个LaunchImage尺寸
- assets/images/: 新增 logo.png(760x144) + logo_icon.png(192x192)
- pubspec.yaml: 新增 assets 声明
- welcome_page.dart: Icons.diamond_rounded → Image.asset('logo_icon.png')
- issuer_login_page.dart: Icons.storefront_rounded → Image.asset('logo_icon.png')
- issuer_dashboard_page.dart: 同上
- settings_page.dart: 同上

### admin-web（Next.js 15）
- public/: favicon.ico/png, logo.png, logo_icon.png, icon-512.png, SVG源文件
- layout.tsx: 更新metadata icons配置
- AdminLayout.tsx: 侧栏inline "G"文字 → <img src="/logo_icon.png">

### miniapp（Taro/React 小程序）
- login/index.tsx: "G"文字Logo → CSS双色分割旋转方块
- share-card/index.tsx: 同上 + 品牌色从#6C5CE7更新为#9B5CF6/#D946EF

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

frontend/admin-app/lib/features/auth/presentation/pages/issuer_login_page.dart

@@ -31,14 +31,13 @@ class _IssuerLoginPageState extends State<IssuerLoginPage> {
               const SizedBox(height: 60),
 
               // Logo
-              Container(
+              ClipRRect(
+                borderRadius: BorderRadius.circular(14),
+                child: Image.asset(
+                  'assets/images/logo_icon.png',
                   width: 56,
                   height: 56,
-                decoration: BoxDecoration(
-                  gradient: AppColors.primaryGradient,
-                  borderRadius: BorderRadius.circular(14),
                 ),
-                child: const Icon(Icons.storefront_rounded, color: Colors.white, size: 28),
               ),
               const SizedBox(height: 24),
 

frontend/admin-app/lib/features/dashboard/presentation/pages/issuer_dashboard_page.dart

@@ -73,7 +73,10 @@ class IssuerDashboardPage extends StatelessWidget {
               color: Colors.white.withValues(alpha: 0.2),
               borderRadius: BorderRadius.circular(12),
             ),
-            child: const Icon(Icons.storefront_rounded, color: Colors.white, size: 24),
+            child: ClipRRect(
+              borderRadius: BorderRadius.circular(10),
+              child: Image.asset('assets/images/logo_icon.png', width: 48, height: 48),
+            ),
           ),
           const SizedBox(width: 14),
           Expanded(

frontend/admin-app/lib/features/settings/presentation/pages/settings_page.dart

@@ -120,14 +120,13 @@ class _SettingsPageState extends State<SettingsPage> {
       color: AppColors.surface,
       child: Row(
         children: [
-          Container(
+          ClipRRect(
+            borderRadius: BorderRadius.circular(14),
+            child: Image.asset(
+              'assets/images/logo_icon.png',
               width: 56,
               height: 56,
-            decoration: BoxDecoration(
-              gradient: AppColors.primaryGradient,
-              borderRadius: BorderRadius.circular(14),
             ),
-            child: const Icon(Icons.storefront_rounded, color: Colors.white, size: 28),
           ),
           const SizedBox(width: 14),
           Expanded(

frontend/admin-app/pubspec.yaml

@@ -29,3 +29,6 @@ dev_dependencies:
 
 flutter:
   uses-material-design: true
+  assets:
+    - assets/images/logo.png
+    - assets/images/logo_icon.png

frontend/admin-web/public/logo-full.svg

@@ -0,0 +1,30 @@
+<svg viewBox="0 0 380 72" xmlns="http://www.w3.org/2000/svg">
+  <defs>
+    <linearGradient id="L" x1="0%" y1="0%" x2="100%" y2="100%">
+      <stop offset="0%" stop-color="#9B5CF6"/>
+      <stop offset="100%" stop-color="#A855F7"/>
+    </linearGradient>
+    <linearGradient id="R" x1="0%" y1="0%" x2="100%" y2="100%">
+      <stop offset="0%" stop-color="#D946EF"/>
+      <stop offset="100%" stop-color="#E11D89"/>
+    </linearGradient>
+    <linearGradient id="EX" x1="0%" y1="0%" x2="100%" y2="0%">
+      <stop offset="0%" stop-color="#D946EF"/>
+      <stop offset="100%" stop-color="#E11D89"/>
+    </linearGradient>
+    <mask id="notch">
+      <rect x="-40" y="-40" width="80" height="80" fill="white"/>
+      <circle cx="0" cy="-26" r="3.5" fill="black"/>
+      <circle cx="0" cy="26" r="3.5" fill="black"/>
+    </mask>
+  </defs>
+  <g transform="translate(36,36)">
+    <g transform="rotate(45)" mask="url(#notch)">
+      <path d="M-20 -26 L0 -26 L-4.5 -1.5 L4.5 1.5 L0 26 L-20 26 Q-26 26 -26 20 L-26 -20 Q-26 -26 -20 -26 Z" fill="url(#L)"/>
+      <path d="M0 -26 L20 -26 Q26 -26 26 -20 L26 20 Q26 26 20 26 L0 26 L4.5 1.5 L-4.5 -1.5 Z" fill="url(#R)"/>
+    </g>
+  </g>
+  <text x="84" y="48" font-family="Sora, sans-serif" font-weight="800" font-size="34" letter-spacing="-1">
+    <tspan fill="#1A103A">GEN</tspan><tspan fill="url(#EX)">EX</tspan>
+  </text>
+</svg>

frontend/admin-web/public/logo.svg

@@ -0,0 +1,23 @@
+<svg viewBox="0 0 72 72" xmlns="http://www.w3.org/2000/svg">
+  <defs>
+    <linearGradient id="L" x1="0%" y1="0%" x2="100%" y2="100%">
+      <stop offset="0%" stop-color="#9B5CF6"/>
+      <stop offset="100%" stop-color="#A855F7"/>
+    </linearGradient>
+    <linearGradient id="R" x1="0%" y1="0%" x2="100%" y2="100%">
+      <stop offset="0%" stop-color="#D946EF"/>
+      <stop offset="100%" stop-color="#E11D89"/>
+    </linearGradient>
+    <mask id="notch">
+      <rect x="-40" y="-40" width="80" height="80" fill="white"/>
+      <circle cx="0" cy="-26" r="3.5" fill="black"/>
+      <circle cx="0" cy="26" r="3.5" fill="black"/>
+    </mask>
+  </defs>
+  <g transform="translate(36,36)">
+    <g transform="rotate(45)" mask="url(#notch)">
+      <path d="M-20 -26 L0 -26 L-4.5 -1.5 L4.5 1.5 L0 26 L-20 26 Q-26 26 -26 20 L-26 -20 Q-26 -26 -20 -26 Z" fill="url(#L)"/>
+      <path d="M0 -26 L20 -26 Q26 -26 26 -20 L26 20 Q26 26 20 26 L0 26 L4.5 1.5 L-4.5 -1.5 Z" fill="url(#R)"/>
+    </g>
+  </g>
+</svg>

frontend/admin-web/src/app/layout.tsx

@@ -6,7 +6,8 @@ export const metadata: Metadata = {
   title: 'Genex Admin - 券金融平台管理后台',
   description: 'Genex 券金融平台运营管理系统',
   icons: {
-    icon: '/favicon.ico',
+    icon: '/favicon.png',
+    apple: '/logo_icon.png',
   },
 };
 

frontend/admin-web/src/layouts/AdminLayout.tsx

@@ -139,19 +139,11 @@ export const AdminLayout: React.FC<{ children: React.ReactNode }> = ({ children
           padding: '0 20px',
           borderBottom: '1px solid var(--color-border-light)',
         }}>
-          <div style={{
-            width: 32, height: 32,
-            background: 'linear-gradient(135deg, #6C5CE7, #9B8FFF)',
-            borderRadius: 'var(--radius-sm)',
-            display: 'flex',
-            alignItems: 'center',
-            justifyContent: 'center',
-            color: 'white',
-            fontWeight: 700,
-            fontSize: 16,
-          }}>
-            G
-          </div>
+          <img
+            src="/logo_icon.png"
+            alt="Genex"
+            style={{ width: 32, height: 32, borderRadius: 'var(--radius-sm)' }}
+          />
           {!collapsed && (
             <span style={{
               marginLeft: 12,

frontend/genex-mobile/lib/features/auth/presentation/pages/welcome_page.dart

@@ -22,18 +22,12 @@ class WelcomePage extends StatelessWidget {
               const Spacer(flex: 2),
 
               // Brand Logo
-              Container(
+              ClipRRect(
+                borderRadius: AppSpacing.borderRadiusXl,
+                child: Image.asset(
+                  'assets/images/logo_icon.png',
                   width: 80,
                   height: 80,
-                decoration: BoxDecoration(
-                  gradient: AppColors.primaryGradient,
-                  borderRadius: AppSpacing.borderRadiusXl,
-                  boxShadow: AppSpacing.shadowPrimary,
-                ),
-                child: const Icon(
-                  Icons.diamond_rounded,
-                  color: Colors.white,
-                  size: 40,
                 ),
               ),
               const SizedBox(height: 24),

frontend/genex-mobile/pubspec.yaml

@@ -30,3 +30,6 @@ dev_dependencies:
 
 flutter:
   uses-material-design: true
+  assets:
+    - assets/images/logo.png
+    - assets/images/logo_icon.png

frontend/miniapp/src/components/share-card/index.tsx

@@ -25,9 +25,10 @@ const ShareCard: React.FC<ShareCardProps> = ({
       {/* Header */}
       <view className="share-header">
         <view className="share-logo">
-          <text className="share-logo-text">G</text>
+          <view className="share-logo-left" />
+          <view className="share-logo-right" />
         </view>
-        <text className="share-brand">Genex · {brand}</text>
+        <text className="share-brand">GENEX · {brand}</text>
       </view>
 
       {/* Coupon Info */}
@@ -69,24 +70,33 @@ CSS:
 .share-header {
   display: flex; align-items: center;
   padding: 24rpx 28rpx;
-  background: linear-gradient(135deg, #6C5CE7, #9B8FFF);
+  background: linear-gradient(135deg, #9B5CF6, #D946EF);
 }
 .share-logo {
-  width: 48rpx; height: 48rpx; background: rgba(255,255,255,0.2);
+  width: 48rpx; height: 48rpx;
   border-radius: 10rpx; display: flex;
   align-items: center; justify-content: center;
+  overflow: hidden; position: relative;
+  transform: rotate(45deg);
+}
+.share-logo-left {
+  width: 50%; height: 100%;
+  background: linear-gradient(135deg, #9B5CF6, #A855F7);
+}
+.share-logo-right {
+  width: 50%; height: 100%;
+  background: linear-gradient(135deg, #D946EF, #E11D89);
 }
-.share-logo-text { color: white; font-weight: 700; font-size: 24rpx; }
 .share-brand { color: white; font-size: 26rpx; font-weight: 600; margin-left: 12rpx; }
 
 .share-body { padding: 28rpx; }
 .share-name { font-size: 32rpx; font-weight: 600; color: #141723; }
 .share-price-row { display: flex; align-items: flex-end; margin-top: 16rpx; }
-.share-price { font-size: 40rpx; font-weight: 700; color: #6C5CE7; }
+.share-price { font-size: 40rpx; font-weight: 700; color: #9B5CF6; }
 .share-face { font-size: 24rpx; color: #A0A8BE; text-decoration: line-through; margin-left: 12rpx; }
 .share-discount {
   margin-left: 12rpx; padding: 4rpx 12rpx;
-  background: linear-gradient(135deg, #6C5CE7, #9B8FFF);
+  background: linear-gradient(135deg, #9B5CF6, #D946EF);
   border-radius: 999rpx;
 }
 .share-discount-text { color: white; font-size: 22rpx; font-weight: 700; }

frontend/miniapp/src/pages/login/index.tsx

@@ -15,9 +15,10 @@ const LoginPage: React.FC = () => {
       {/* Logo */}
       <view className="logo-section">
         <view className="logo-box">
-          <text className="logo-text">G</text>
+          <view className="logo-left" />
+          <view className="logo-right" />
         </view>
-        <text className="app-name">Genex</text>
+        <text className="app-name">GENEX</text>
         <text className="app-slogan">{t('app_slogan')}</text>
       </view>
 
@@ -83,11 +84,18 @@ CSS:
 }
 .logo-box {
   width: 120rpx; height: 120rpx;
-  background: linear-gradient(135deg, #6C5CE7, #9B8FFF);
   border-radius: 28rpx;
   display: flex; align-items: center; justify-content: center;
+  overflow: hidden; transform: rotate(45deg);
+}
+.logo-left {
+  width: 50%; height: 100%;
+  background: linear-gradient(135deg, #9B5CF6, #A855F7);
+}
+.logo-right {
+  width: 50%; height: 100%;
+  background: linear-gradient(135deg, #D946EF, #E11D89);
 }
-.logo-text { color: white; font-size: 48rpx; font-weight: 700; }
 .app-name { font-size: 40rpx; font-weight: 700; color: #141723; margin-top: 24rpx; }
 .app-slogan { font-size: 26rpx; color: #A0A8BE; margin-top: 8rpx; }
 

frontend/mobile/lib/features/auth/presentation/pages/welcome_page.dart

@@ -22,18 +22,12 @@ class WelcomePage extends StatelessWidget {
               const Spacer(flex: 2),
 
               // Brand Logo
-              Container(
+              ClipRRect(
+                borderRadius: AppSpacing.borderRadiusXl,
+                child: Image.asset(
+                  'assets/images/logo_icon.png',
                   width: 80,
                   height: 80,
-                decoration: BoxDecoration(
-                  gradient: AppColors.primaryGradient,
-                  borderRadius: AppSpacing.borderRadiusXl,
-                  boxShadow: AppSpacing.shadowPrimary,
-                ),
-                child: const Icon(
-                  Icons.diamond_rounded,
-                  color: Colors.white,
-                  size: 40,
                 ),
               ),
               const SizedBox(height: 24),

frontend/mobile/pubspec.yaml

@@ -29,3 +29,6 @@ dev_dependencies:
 
 flutter:
   uses-material-design: true
+  assets:
+    - assets/images/logo.png
+    - assets/images/logo_icon.png

logo/genex-04.svg

@@ -0,0 +1,30 @@
+<svg viewBox="0 0 380 72" xmlns="http://www.w3.org/2000/svg">
+  <defs>
+    <linearGradient id="L" x1="0%" y1="0%" x2="100%" y2="100%">
+      <stop offset="0%" stop-color="#9B5CF6"/>
+      <stop offset="100%" stop-color="#A855F7"/>
+    </linearGradient>
+    <linearGradient id="R" x1="0%" y1="0%" x2="100%" y2="100%">
+      <stop offset="0%" stop-color="#D946EF"/>
+      <stop offset="100%" stop-color="#E11D89"/>
+    </linearGradient>
+    <linearGradient id="EX" x1="0%" y1="0%" x2="100%" y2="0%">
+      <stop offset="0%" stop-color="#D946EF"/>
+      <stop offset="100%" stop-color="#E11D89"/>
+    </linearGradient>
+    <mask id="notch">
+      <rect x="-40" y="-40" width="80" height="80" fill="white"/>
+      <circle cx="0" cy="-26" r="3.5" fill="black"/>
+      <circle cx="0" cy="26" r="3.5" fill="black"/>
+    </mask>
+  </defs>
+  <g transform="translate(36,36)">
+    <g transform="rotate(45)" mask="url(#notch)">
+      <path d="M-20 -26 L0 -26 L-4.5 -1.5 L4.5 1.5 L0 26 L-20 26 Q-26 26 -26 20 L-26 -20 Q-26 -26 -20 -26 Z" fill="url(#L)"/>
+      <path d="M0 -26 L20 -26 Q26 -26 26 -20 L26 20 Q26 26 20 26 L0 26 L4.5 1.5 L-4.5 -1.5 Z" fill="url(#R)"/>
+    </g>
+  </g>
+  <text x="84" y="48" font-family="Sora, sans-serif" font-weight="800" font-size="34" letter-spacing="-1">
+    <tspan fill="#1A103A">GEN</tspan><tspan fill="url(#EX)">EX</tspan>
+  </text>
+</svg>

logo/genex-icon.svg

@@ -0,0 +1,23 @@
+<svg viewBox="0 0 72 72" xmlns="http://www.w3.org/2000/svg">
+  <defs>
+    <linearGradient id="L" x1="0%" y1="0%" x2="100%" y2="100%">
+      <stop offset="0%" stop-color="#9B5CF6"/>
+      <stop offset="100%" stop-color="#A855F7"/>
+    </linearGradient>
+    <linearGradient id="R" x1="0%" y1="0%" x2="100%" y2="100%">
+      <stop offset="0%" stop-color="#D946EF"/>
+      <stop offset="100%" stop-color="#E11D89"/>
+    </linearGradient>
+    <mask id="notch">
+      <rect x="-40" y="-40" width="80" height="80" fill="white"/>
+      <circle cx="0" cy="-26" r="3.5" fill="black"/>
+      <circle cx="0" cy="26" r="3.5" fill="black"/>
+    </mask>
+  </defs>
+  <g transform="translate(36,36)">
+    <g transform="rotate(45)" mask="url(#notch)">
+      <path d="M-20 -26 L0 -26 L-4.5 -1.5 L4.5 1.5 L0 26 L-20 26 Q-26 26 -26 20 L-26 -20 Q-26 -26 -20 -26 Z" fill="url(#L)"/>
+      <path d="M0 -26 L20 -26 Q26 -26 26 -20 L26 20 Q26 26 20 26 L0 26 L4.5 1.5 L-4.5 -1.5 Z" fill="url(#R)"/>
+    </g>
+  </g>
+</svg>