feat: 为所有终端添加平台显示功能

- 新增 frontend/lib/platforms.ts 共享平台配置模块
- 支持6个平台: 抖音、小红书、B站、快手、微博、微信视频号
- 品牌方终端: 项目看板、项目详情、终审台列表添加平台显示
- 代理商终端: 工作台概览、审核台、Brief配置、达人管理、
  数据报表、消息中心、申诉处理添加平台显示
- 达人端: 任务列表添加平台显示
- 统一使用彩色头部条样式展示平台信息

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

frontend/components/layout/DesktopLayout.tsx

@@ -14,10 +14,12 @@ export function DesktopLayout({
   className = '',
 }: DesktopLayoutProps) {
   return (
-    <div className={`min-h-screen bg-bg-page flex ${className}`}>
+    <div className={`h-screen bg-bg-page flex overflow-hidden ${className}`}>
       <Sidebar role={role} />
-      <main className="flex-1 ml-[260px] p-8 overflow-auto">
-        {children}
+      <main className="flex-1 ml-[260px] p-8 overflow-y-auto overflow-x-hidden">
+        <div className="min-h-full">
+          {children}
+        </div>
       </main>
     </div>
   )

frontend/components/layout/MobileLayout.tsx

@@ -19,10 +19,12 @@ export function MobileLayout({
   className = '',
 }: MobileLayoutProps) {
   return (
-    <div className={`min-h-screen bg-bg-page flex flex-col overflow-x-hidden ${className}`}>
+    <div className={`h-screen bg-bg-page flex flex-col overflow-hidden ${className}`}>
       {showStatusBar && <StatusBar />}
-      <main className={`flex-1 ${showBottomNav ? 'pb-[95px]' : ''}`}>
-        {children}
+      <main className={`flex-1 overflow-y-auto overflow-x-hidden ${showBottomNav ? 'pb-[80px]' : ''}`}>
+        <div className="min-h-full">
+          {children}
+        </div>
       </main>
       {showBottomNav && <BottomNav role={role} />}
     </div>

frontend/components/layout/ResponsiveLayout.tsx

@@ -37,7 +37,7 @@ export function ResponsiveLayout({
   const closeSidebar = () => setSidebarOpen(false)
 
   return (
-    <div className={cn('min-h-screen bg-bg-page', className)}>
+    <div className={cn('h-screen bg-bg-page overflow-hidden', className)}>
       {/* 移动端：汉堡菜单按钮 */}
       {isMobile && !sidebarOpen && (
         <button
@@ -84,11 +84,13 @@ export function ResponsiveLayout({
       {/* 主内容区 */}
       <main
         className={cn(
-          'min-h-screen transition-all duration-300',
+          'h-full overflow-y-auto overflow-x-hidden transition-all duration-300',
           isMobile ? 'ml-0 pt-16 px-4 pb-6' : 'ml-[260px] p-8'
         )}
       >
-        {children}
+        <div className="min-h-full">
+          {children}
+        </div>
       </main>
     </div>
   )

frontend/components/ui/Modal.tsx

@@ -25,7 +25,15 @@ const sizeStyles = {
   md: 'max-w-md',
   lg: 'max-w-lg',
   xl: 'max-w-xl',
-  full: 'max-w-[90vw] max-h-[90vh]',
+  full: 'max-w-[90vw]',
+};
+
+const bodyMaxHeightStyles = {
+  sm: 'max-h-[50vh]',
+  md: 'max-h-[60vh]',
+  lg: 'max-h-[65vh]',
+  xl: 'max-h-[70vh]',
+  full: 'max-h-[75vh]',
 };
 
 export const Modal: React.FC<ModalProps> = ({
@@ -105,7 +113,7 @@ export const Modal: React.FC<ModalProps> = ({
         )}
 
         {/* Body */}
-        <div className="px-5 py-4 max-h-[60vh] overflow-y-auto">
+        <div className={`px-5 py-4 overflow-y-auto ${bodyMaxHeightStyles[size]}`}>
           {children}
         </div>