feat(用户中心): 添加登录状态判断及登录按钮

在用户中心页面添加了登录状态判断逻辑，未登录时显示登录按钮和提示信息，已登录时显示菜单。同时优化了头像和昵称的默认显示内容，提升用户体验。

pages/index/center.vue

@@ -5,11 +5,11 @@
 
 		<view class="head">
 			<view class="headImage">
-				<image :src="userInfo.headImage" mode="aspectFill"></image>
+				<image :src="userInfo.headImage || '/static/image/center/default_avatar.png'" mode="aspectFill"></image>
 			</view>
 			<view class="info">
 				<view class="name">
-					{{ userInfo.nickName || '微信用户'}}
+					{{ userInfo.nickName || '未登录用户'}}
 				</view>
 				<view class="tips"
 				v-if="userInfo.createTime">
@@ -21,7 +21,14 @@
 			</view>
 		</view>
 
-		<view class="line">
+		<!-- 未登录状态显示登录按钮 -->
+		<view v-if="!isLogin" class="login-container">
+			<button class="login-btn" @click="toLogin">立即登录</button>
+			<view class="login-tips">登录后查看更多功能</view>
+		</view>
+
+		<!-- 已登录状态显示菜单 -->
+		<view class="line" v-if="isLogin">
 			<uv-cell-group>
 				
 				<!-- 我的收藏 -->
@@ -104,6 +111,9 @@
 	export default {
 		computed: {
 			...mapState(['userInfo']),
+			isLogin() {
+				return this.userInfo && this.userInfo.id
+			}
 		},
 		data() {
 			return {
@@ -111,10 +121,14 @@
 			}
 		},
 		onShow() {
-			this.$store.commit('getUserInfo')
+			if(uni.getStorageSync('token')){
+				this.$store.commit('getUserInfo')
+			}
 		},
 		methods: {
-
+			toLogin() {
+				this.$utils.navigateTo('/pages_order/auth/wxLogin')
+			}
 		}
 	}
 </script>
@@ -180,5 +194,27 @@
 		}
 	}
 
+	.login-container {
+		display: flex;
+		flex-direction: column;
+		align-items: center;
+		margin: 60rpx 30rpx;
+	}
+	
+	.login-btn {
+		width: 80%;
+		height: 80rpx;
+		line-height: 80rpx;
+		background-color: $uni-color;
+		color: #fff;
+		border-radius: 40rpx;
+		font-size: 32rpx;
+		margin-bottom: 20rpx;
+	}
+	
+	.login-tips {
+		font-size: 26rpx;
+		color: #999;
+	}
 	
 </style>

pages/index/index.vue

@@ -37,9 +37,9 @@
 			
 			<view class="index_box">
 				
-				<view class="image-box">
+				<view class="image-box"
+				@click="$utils.navigateTo('/pages_order/service/newsList')">
 					<image :src="config_new_image"
-					@click="$utils.navigateTo('/pages_order/service/newsList')"
 					class="image" mode="aspectFill"></image>
 					
 					<view class="image-text">