feat: 新增运动节拍训练工具套件与子工具页面

新增运动节拍RepClock全套小程序页面、后端API与数据库服务，新增subhub子工具汇总页面，优化全局主页样式与配置，为web静态资源添加版本缓存参数，补充配套调试脚本

miniprogram/mp_time_assistant/pages/subhub/subhub.wxss

@@ -0,0 +1,23 @@
+.hero-card {
+  margin: 4rpx 24rpx 36rpx;
+  padding: 32rpx 30rpx;
+  background: linear-gradient(145deg, rgba(108, 122, 224, 0.22), rgba(176, 107, 224, 0.16));
+  border: 1px solid rgba(140, 150, 240, 0.24);
+  border-radius: 28rpx;
+  display: flex;
+  align-items: center;
+  gap: 26rpx;
+  box-shadow: 0 14rpx 36rpx rgba(0,0,0,0.28);
+}
+.hero-icon { width: 96rpx; height: 96rpx; flex: none; border-radius: 24rpx; background: rgba(255,255,255,0.08); display: flex; align-items: center; justify-content: center; }
+.hero-emoji { font-size: 54rpx; }
+.hero-title { font-size: 30rpx; font-weight: 700; color: #efeffe; letter-spacing: 0.5rpx; margin-bottom: 8rpx; }
+.hero-desc { font-size: 24rpx; color: #a6a9d0; }
+
+.footer {
+  margin: 80rpx 0 40rpx;
+  text-align: center;
+  letter-spacing: 1rpx;
+  color: #5a5e82;
+  font-size: 22rpx;
+}