refactor: 统一剪贴板复制功能到 useClipboard 组合式函数

将各个组件和视图中重复的剪贴板复制逻辑提取到 useClipboard 组合式函数。
增加 showToast 参数支持静默复制，减少代码重复，提高维护性。

frontend/src/views/user/ModelCatalog.vue

@@ -342,6 +342,7 @@ import {
   Plus,
 } from 'lucide-vue-next'
 import { useToast } from '@/composables/useToast'
+import { useClipboard } from '@/composables/useClipboard'
 import {
   Card,
   Table,
@@ -370,6 +371,7 @@ import { useRowClick } from '@/composables/useRowClick'
 import { log } from '@/utils/logger'
 
 const { success, error: showError } = useToast()
+const { copyToClipboard } = useClipboard()
 
 // 状态
 const loading = ref(false)
@@ -565,16 +567,6 @@ function hasTieredPricing(model: PublicGlobalModel): boolean {
   return (tiered?.tiers?.length || 0) > 1
 }
 
-async function copyToClipboard(text: string) {
-  try {
-    await navigator.clipboard.writeText(text)
-    success('已复制')
-  } catch (err) {
-    log.error('复制失败:', err)
-    showError('复制失败')
-  }
-}
-
 onMounted(() => {
   refreshData()
 })

frontend/src/views/user/components/UserModelDetailDrawer.vue

@@ -352,6 +352,7 @@ import {
 } from 'lucide-vue-next'
 import { useEscapeKey } from '@/composables/useEscapeKey'
 import { useToast } from '@/composables/useToast'
+import { useClipboard } from '@/composables/useClipboard'
 import Card from '@/components/ui/card.vue'
 import Badge from '@/components/ui/badge.vue'
 import Button from '@/components/ui/button.vue'
@@ -375,6 +376,7 @@ const emit = defineEmits<{
 }>()
 
 const { success: showSuccess, error: showError } = useToast()
+const { copyToClipboard } = useClipboard()
 
 interface Props {
   model: PublicGlobalModel | null
@@ -408,15 +410,6 @@ function handleClose() {
   emit('update:open', false)
 }
 
-async function copyToClipboard(text: string) {
-  try {
-    await navigator.clipboard.writeText(text)
-    showSuccess('已复制')
-  } catch {
-    showError('复制失败')
-  }
-}
-
 function getFirstTierPrice(
   tieredPricing: TieredPricingConfig | undefined | null,
   priceKey: 'input_price_per_1m' | 'output_price_per_1m' | 'cache_creation_price_per_1m' | 'cache_read_price_per_1m'