feat(uniapp): 加开发用「练一练」悬浮入口

- 新组件 dev-training-entry：右下角圆形悬浮按钮，带 DEV 标签
- 仅在 isDevMode() 为真时显示，上线打包自动隐藏
- 挂载到首页和个人中心，方便快速跳转 /pages/training/index 测试

后续走装修系统给 user 页配「练一练」服务图标后即可移除此组件

Co-authored-by: Cursor <cursoragent@cursor.com>

uniapp/src/components/dev-training-entry/index.vue

@@ -0,0 +1,75 @@
+<template>
+    <view v-if="visible" class="dev-training-entry" @click="goTraining">
+        <view class="entry-icon">💪</view>
+        <view class="entry-text">练一练</view>
+        <view class="entry-tag">DEV</view>
+    </view>
+</template>
+
+<script setup lang="ts">
+import { ref } from 'vue'
+import { isDevMode } from '@/utils/env'
+
+const props = withDefaults(
+    defineProps<{
+        bottom?: number
+    }>(),
+    { bottom: 200 },
+)
+
+const visible = ref(isDevMode())
+
+const goTraining = () => {
+    uni.navigateTo({ url: '/pages/training/index' })
+}
+</script>
+
+<style lang="scss" scoped>
+.dev-training-entry {
+    position: fixed;
+    right: 24rpx;
+    bottom: v-bind('props.bottom + "rpx"');
+    z-index: 999;
+
+    width: 110rpx;
+    height: 110rpx;
+    border-radius: 50%;
+    background: linear-gradient(135deg, #22c55e, #16a34a);
+    box-shadow: 0 6rpx 20rpx rgba(34, 197, 94, 0.4);
+
+    display: flex;
+    flex-direction: column;
+    align-items: center;
+    justify-content: center;
+
+    transition: transform 0.2s;
+
+    &:active {
+        transform: scale(0.92);
+    }
+
+    .entry-icon {
+        font-size: 40rpx;
+        line-height: 1;
+    }
+
+    .entry-text {
+        font-size: 18rpx;
+        color: #fff;
+        margin-top: 4rpx;
+        line-height: 1;
+    }
+
+    .entry-tag {
+        position: absolute;
+        top: -8rpx;
+        right: -8rpx;
+        background: #ef4444;
+        color: #fff;
+        font-size: 16rpx;
+        padding: 2rpx 8rpx;
+        border-radius: 8rpx;
+        line-height: 1.4;
+    }
+}
+</style>