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/Dashboard/Center.js

@@ -400,13 +400,13 @@ export default function CenterDashboard() {
                       {followingEvents.length}
                     </Badge>
                   </HStack>
-                  <Button
-                    size="sm"
+                  <IconButton
+                    icon={<FiPlus />}
                     variant="ghost"
+                    size="sm"
                     onClick={() => navigate('/community')}
-                  >
-                    查看更多
-                  </Button>
+                    aria-label="添加关注事件"
+                  />
                 </Flex>
               </CardHeader>
               <CardBody pt={0} flex="1" overflowY="auto">