feat(listings): 排序交互升级为双向翻转并对齐双端体验

- PC端交互：HomeView 排序按钮支持点击切换升降序翻转（比例、哈夫币、AWM数量、合并价格为单个价格项），并带有高低方向箭头（▲/▼）高亮指示
- 移动端交互：MobileHomeView 菜单提供清晰的双向文案（如「比例从高到低 / 比例从低到高」），且点击当前选中项时支持自动翻转方向，顶部工具栏标题紧凑对齐
- 后端排序：public_filter 与 public_query 完整支持 ratioDesc/ratioAsc、priceAsc/priceDesc、coinDesc/coinAsc、awmDesc/awmAsc
- 验证方式：新增并运行 TestSortPublicListingsByRatio 包含升序/降序多断言，全量运行 ./scripts/check.sh 门禁全绿通过

frontend/src/features/listings/views/MobileHomeView.vue

@@ -123,14 +123,23 @@ const mobilePageSize = 10
 let listingRequestSeq = 0
 let searchDebounceTimer: ReturnType<typeof setTimeout> | null = null
 
-const sortOptions = [
-  { key: 'recommended', label: '综合推荐' },
-  { key: 'ratioDesc', label: '比例排序' },
-  { key: 'coinDesc', label: '哈夫币' },
-  { key: 'awmDesc', label: 'AWM数量' },
-  { key: 'priceAsc', label: '价格最低' },
-  { key: 'priceDesc', label: '价格最高' },
-  { key: 'published', label: '最新发布' },
+interface MobileSortOption {
+  key: string
+  label: string
+  shortLabel: string
+}
+
+const sortOptions: MobileSortOption[] = [
+  { key: 'recommended', label: '综合推荐', shortLabel: '综合推荐' },
+  { key: 'ratioDesc', label: '比例从高到低', shortLabel: '比例最高' },
+  { key: 'ratioAsc', label: '比例从低到高', shortLabel: '比例最低' },
+  { key: 'priceAsc', label: '价格从低到高', shortLabel: '价格最低' },
+  { key: 'priceDesc', label: '价格从高到低', shortLabel: '价格最高' },
+  { key: 'coinDesc', label: '哈夫币从多到少', shortLabel: '哈夫币最多' },
+  { key: 'coinAsc', label: '哈夫币从少到多', shortLabel: '哈夫币最少' },
+  { key: 'awmDesc', label: 'AWM数量从多到少', shortLabel: 'AWM最多' },
+  { key: 'awmAsc', label: 'AWM数量从少到多', shortLabel: 'AWM最少' },
+  { key: 'published', label: '最新发布', shortLabel: '最新发布' },
 ]
 
 const zoneOptions = [
@@ -146,7 +155,7 @@ const zoneOptions = [
 const rangePresets = defaultRangePresets
 
 const activeSortLabel = computed(
-  () => sortOptions.find(option => option.key === activeSort.value)?.label || '综合排序'
+  () => sortOptions.find(option => option.key === activeSort.value)?.shortLabel || '综合推荐'
 )
 
 async function handleSupportClick() {
@@ -552,6 +561,23 @@ function toggleSortPanel() {
 }
 
 function selectSort(sortKey: string) {
+  if (activeSort.value === sortKey) {
+    const flipMap: Record<string, string> = {
+      ratioDesc: 'ratioAsc',
+      ratioAsc: 'ratioDesc',
+      priceAsc: 'priceDesc',
+      priceDesc: 'priceAsc',
+      coinDesc: 'coinAsc',
+      coinAsc: 'coinDesc',
+      awmDesc: 'awmAsc',
+      awmAsc: 'awmDesc',
+    }
+    if (flipMap[sortKey]) {
+      activeSort.value = flipMap[sortKey]
+      sortOpen.value = false
+      return
+    }
+  }
   activeSort.value = sortKey
   sortOpen.value = false
 }