fix(UI): Profile 取消按钮样式、HotEvents 轮播箭头、Dashboard 按钮优化

- Profile: 取消按钮添加深色主题样式 (color, borderColor, hover)
- HotEvents: 轮播箭头添加 user-select: none 防止连续点击选中文本
- Dashboard: "查看更多"按钮改为图标按钮 (IconButton + FiPlus)

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

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

src/views/Community/components/HotEvents/HotEvents.css

@@ -54,6 +54,7 @@
     box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15) !important;
     transition: all 0.3s ease !important;
     z-index: 10 !important;
+    user-select: none !important;  /* 防止连续点击时选中文本 */
 }
 
 .custom-carousel-arrow:hover {