fix(mp): 修正 design token 字号对齐原型 + ContentCard margin prop

- tokens.scss: 修正字号 token 对齐 18 份原型稿 fontSize 统计
  --tk-font-h1: 26→28px, --tk-font-h2: 24→22px
  --tk-font-body-lg: 28→18px, --tk-font-body: 22→16px
  --tk-font-body-sm: 16→14px
  elder-mode 同步重新计算比例系数
- ContentCard: 新增 margin prop ('none'|'md')，margin-bottom
  从 CSS 类移至 inline style，支持列表容器内无间距模式
- Profile 页: 用户卡片添加 profile-user-card flex 布局
  菜单组/积分卡片使用 margin="none"，修复布局对齐
- Login 页: SCSS 全部改为 design token 引用

apps/miniprogram/src/pages/profile/index.tsx

@@ -135,7 +135,7 @@ export default function Profile() {
     <PageShell padding="md" safeBottom={false} scroll={false} className={`profile-page ${modeClass}`}>
       {/* 用户信息卡片 */}
       {isGuest ? (
-        <ContentCard variant="elevated" onPress={navigateToLogin}>
+        <ContentCard variant="elevated" onPress={navigateToLogin} className="profile-user-card">
           <View className='profile-avatar profile-avatar--guest'>
             <Text className='profile-avatar-char'>?</Text>
           </View>
@@ -147,7 +147,7 @@ export default function Profile() {
         </ContentCard>
       ) : (
         <>
-          <ContentCard variant="elevated">
+          <ContentCard variant="elevated" className="profile-user-card">
             <View className='profile-avatar'>
               <Text className='profile-avatar-char'>{displayInitial}</Text>
             </View>
@@ -165,13 +165,17 @@ export default function Profile() {
             <Loading />
           ) : (
           <View className='profile-stats-row'>
-            <ContentCard padding="sm">
-              <Text className='stat-value stat-pri'>{(pointsAccount?.balance ?? 0).toLocaleString()}</Text>
-              <Text className='stat-label'>健康积分</Text>
+            <ContentCard padding="sm" margin="none">
+              <View className='stat-card'>
+                <Text className='stat-value stat-pri'>{(pointsAccount?.balance ?? 0).toLocaleString()}</Text>
+                <Text className='stat-label'>健康积分</Text>
+              </View>
             </ContentCard>
-            <ContentCard padding="sm">
-              <Text className='stat-value stat-acc'>{checkinInfo?.consecutive_days ?? 0}<Text className='stat-unit'>天</Text></Text>
-              <Text className='stat-label'>连续打卡</Text>
+            <ContentCard padding="sm" margin="none">
+              <View className='stat-card'>
+                <Text className='stat-value stat-acc'>{checkinInfo?.consecutive_days ?? 0}<Text className='stat-unit'>天</Text></Text>
+                <Text className='stat-label'>连续打卡</Text>
+              </View>
             </ContentCard>
           </View>
           )}
@@ -183,6 +187,7 @@ export default function Profile() {
         <View className='menu-group'>
           <ContentCard
             padding="none"
+            margin="none"
             onPress={() => Taro.navigateTo({ url: '/pages/pkg-profile/notifications/index' })}
           >
             <View className='menu-item'>
@@ -205,7 +210,7 @@ export default function Profile() {
       {groups.map((group) => (
         <View className='menu-group' key={group.title}>
           <Text className='menu-group-title'>{group.title}</Text>
-          <ContentCard padding="none">
+          <ContentCard padding="none" margin="none">
             {group.items.map((item, idx) => (
               <View
                 className='menu-item'