feat(miniprogram): 老年友好版本全面重设计 — 5→4 Tab + 首页/健康/消息/我的重写

- TabBar 从 5 Tab 调整为 4 Tab（首页/健康/消息/我的）
- 首页重写为 5 区域布局：问候+进度环+体征2x2+待办+快捷操作
- 健康页重写：体征录入大输入框+趋势柱状图+BLE设备卡片
- 新建消息页：咨询对话+系统通知双 Tab
- 我的页调整：菜单高度64px+新增积分商城入口
- 设计系统更新：色彩对比度提升(WCAG AA)+触控参数+老年友好 mixin
- 新增 ProgressRing 组件（CSS conic-gradient 实现）
- 修复 diagnoses 页面 $suc-l 未定义变量

apps/miniprogram/src/components/ProgressRing.scss

@@ -0,0 +1,29 @@
+@import '../styles/variables.scss';
+
+.progress-ring {
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  flex-shrink: 0;
+}
+
+.progress-ring-inner {
+  background: $card;
+  border-radius: 50%;
+  display: flex;
+  align-items: baseline;
+  justify-content: center;
+}
+
+.progress-ring-percent {
+  font-family: 'Georgia', 'Times New Roman', serif;
+  font-size: 22px;
+  font-weight: bold;
+  line-height: 1;
+}
+
+.progress-ring-unit {
+  font-size: 12px;
+  font-weight: 600;
+  line-height: 1;
+}

apps/miniprogram/src/components/ProgressRing.tsx

@@ -0,0 +1,40 @@
+import { View, Text } from '@tarojs/components';
+import './ProgressRing.scss';
+
+interface ProgressRingProps {
+  percent: number;
+  size?: number;
+  strokeWidth?: number;
+  color?: string;
+  trackColor?: string;
+}
+
+export default function ProgressRing({
+  percent,
+  size = 72,
+  strokeWidth = 7,
+  color = '#C4623A',
+  trackColor = '#E8E2DC',
+}: ProgressRingProps) {
+  const clamped = Math.max(0, Math.min(100, percent));
+  const innerSize = size - strokeWidth * 2;
+
+  return (
+    <View
+      className='progress-ring'
+      style={`width:${size}px;height:${size}px;background:conic-gradient(${color} ${clamped}%, ${trackColor} ${clamped}%);border-radius:50%;padding:${strokeWidth}px;`}
+    >
+      <View
+        className='progress-ring-inner'
+        style={`width:${innerSize}px;height:${innerSize}px;`}
+      >
+        <Text className='progress-ring-percent' style={`color:${color};`}>
+          {clamped}
+        </Text>
+        <Text className='progress-ring-unit' style={`color:${color};`}>
+          %
+        </Text>
+      </View>
+    </View>
+  );
+}