refactor: 移除暗色模式相关代码，使用固定浅色主题

- DeepAnalysisTab: 移除 useColorModeValue，使用固定颜色值
- NewsEventsTab: 移除 useColorModeValue，简化 hover 颜色
- FinancialPanorama: 移除 useColorMode/useColorModeValue
- MarketDataView: 移除 dark 主题配置，简化颜色逻辑
- StockQuoteCard: 移除 useColorModeValue，使用固定颜色

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

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

src/views/Company/components/CompanyOverview/NewsEventsTab.js

@@ -18,7 +18,6 @@ import {
   Tag,
   Center,
   Spinner,
-  useColorModeValue,
 } from "@chakra-ui/react";
 import { SearchIcon } from "@chakra-ui/icons";
 import {
@@ -67,9 +66,6 @@ const NewsEventsTab = ({
   onPageChange,
   cardBg,
 }) => {
-  // 颜色模式值需要在组件顶层调用
-  const hoverBg = useColorModeValue("gray.50", "gray.700");
-
   // 事件类型图标映射
   const getEventTypeIcon = (eventType) => {
     const iconMap = {
@@ -233,7 +229,7 @@ const NewsEventsTab = ({
                         key={event.id || idx}
                         variant="outline"
                         _hover={{
-                          bg: hoverBg,
+                          bg: "gray.50",
                           shadow: "md",
                           borderColor: "blue.300",
                         }}