refactor(components): 迁移毛玻璃效果到统一配置

- ImagePreviewModal: 使用 GLASS_BLUR.sm 替代 blur(10px)
- SubscriptionContentNew: 使用 GLASS_BLUR.sm 替代 blur(10px)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

src/components/ImagePreviewModal/index.js

@@ -100,7 +100,7 @@ const ImagePreviewModal = ({ isOpen, onClose, images = [], initialIndex = 0 }) =
 
   return (
     <Modal isOpen={isOpen} onClose={handleClose} size="full" isCentered>
-      <ModalOverlay bg="blackAlpha.900" backdropFilter="blur(10px)" />
+      <ModalOverlay bg="blackAlpha.900" backdropFilter={GLASS_BLUR.sm} />
       <ModalContent bg="transparent" boxShadow="none" m="0">
         <ModalCloseButton
           size="lg"

src/components/Subscription/SubscriptionContentNew.tsx

@@ -1393,7 +1393,7 @@ export default function SubscriptionContentNew() {
 
       {/* 支付模态框 */}
       <Modal isOpen={isOpen} onClose={onClose} size="lg" isCentered>
-        <ModalOverlay bg="rgba(0, 0, 0, 0.8)" backdropFilter="blur(10px)" />
+        <ModalOverlay bg="rgba(0, 0, 0, 0.8)" backdropFilter={GLASS_BLUR.sm} />
         <ModalContent bg="#1e1e1e" borderRadius="2xl" border="1px solid rgba(255, 255, 255, 0.1)">
           <ModalHeader color="white">
             {paymentMethod === 'alipay' ? '支付宝支付' : '微信支付'}