feat(ValueForum): 优化页面布局和加载状态

- 添加响应式左右 padding
- 使用 PageLoader 统一加载样式
- 修复预测市场数据格式处理

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

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

src/views/ValueForum/index.js

@@ -16,7 +16,6 @@ import {
   InputGroup,
   InputLeftElement,
   Select,
-  Spinner,
   Center,
   useDisclosure,
   Flex,
@@ -38,6 +37,7 @@ import PredictionTopicCard from './components/PredictionTopicCard';
 import CreatePostModal from './components/CreatePostModal';
 import CreatePredictionModal from './components/CreatePredictionModal';
 import PredictionGuideModal from './components/PredictionGuideModal';
+import PageLoader from '@components/Loading/PageLoader';
 
 const MotionBox = motion(Box);
 
@@ -97,10 +97,15 @@ const ValueForum = () => {
       setLoading(true);
       const response = await getTopics({ status: 'active', sort_by: sortBy });
       if (response.success) {
-        setPredictionTopics(response.data);
+        // 支持两种返回格式：直接数组或带分页的对象
+        const topicsData = Array.isArray(response.data)
+          ? response.data
+          : (response.data?.topics || []);
+        setPredictionTopics(topicsData);
       }
     } catch (error) {
       console.error('获取预测话题失败:', error);
+      setPredictionTopics([]);
     } finally {
       setLoading(false);
     }
@@ -153,8 +158,8 @@ const ValueForum = () => {
       pt="80px"
       pb="20"
     >
-      {/* padding 由 MainLayout 统一设置 */}
-      <Box>
+      {/* 内容区域 */}
+      <Box px={{ base: "4", md: "6", lg: "8" }} maxW="1600px" mx="auto">
         {/* 顶部横幅 */}
         <MotionBox
           initial={{ opacity: 0, y: -20 }}
@@ -345,17 +350,7 @@ const ValueForum = () => {
             {/* 普通帖子标签页 */}
             <TabPanel p="0">
               {loading && page === 1 ? (
-                <Center py="20">
-                  <VStack spacing="4">
-                    <Spinner
-                      size="xl"
-                      thickness="4px"
-                      speed="0.8s"
-                      color={forumColors.primary[500]}
-                    />
-                    <Text color={forumColors.text.secondary}>加载中...</Text>
-                  </VStack>
-                </Center>
+                <PageLoader inline />
               ) : posts.length === 0 ? (
                 <Center py="20">
                   <VStack spacing="4">
@@ -420,17 +415,7 @@ const ValueForum = () => {
             {/* 预测市场标签页 */}
             <TabPanel p="0">
               {loading ? (
-                <Center py="20">
-                  <VStack spacing="4">
-                    <Spinner
-                      size="xl"
-                      thickness="4px"
-                      speed="0.8s"
-                      color={forumColors.primary[500]}
-                    />
-                    <Text color={forumColors.text.secondary}>加载中...</Text>
-                  </VStack>
-                </Center>
+                <PageLoader inline />
               ) : predictionTopics.length === 0 ? (
                 <Center py="20">
                   <VStack spacing="4">