refactor: 大规模模块拆分与代码精简，新增 ai-pipeline/data-contracts 独立 crate

- 新增 aether-ai-pipeline 和 aether-data-contracts crate，将 pipeline 逻辑与数据契约从 gateway 中解耦
- 重构 admin handlers：拆分单体模块为 auth/billing/endpoint/features/model/observability/provider/system 等独立子模块
- 合并 chat/cli 重复代码路径：精简 conversion、finalize、planner 中的 sync/chat/cli 分支
- 重构 scheduler/executor/data 层，引入 facade 模式降低模块间耦合
- 移除冗余的 intent 模块，将 plan_fallback/policy/stream_path/sync_path 迁移至 executor
- 前端适配：调整 admin API 调用和 provider 模型测试对话框

frontend/src/features/providers/components/EndpointFormDialog.vue

@@ -205,7 +205,7 @@
                       请求体
                     </Button>
                     <Button
-                      v-if="isFixedProvider"
+                      v-if="isFixedProvider && hasDefaultBodyRules(endpoint.api_format)"
                       variant="ghost"
                       size="sm"
                       class="h-7 text-xs px-2"
@@ -1240,11 +1240,21 @@ const deleteConfirmDescription = computed(() => {
   return `确定要删除 ${formatLabel} 端点吗？关联密钥将移除对该 API 格式的支持。`
 })
 
+function defaultBodyRulesCacheKey(apiFormat: string): string {
+  const providerType = (props.provider?.provider_type || '').toLowerCase()
+  return providerType ? `${apiFormat}:${providerType}` : apiFormat
+}
+
+function hasDefaultBodyRules(apiFormat: string): boolean {
+  const cacheKey = defaultBodyRulesCacheKey(apiFormat)
+  if (!defaultBodyRulesLoaded.value[cacheKey]) return false
+  return (defaultBodyRulesByFormat.value[cacheKey]?.length || 0) > 0
+}
+
 async function loadDefaultBodyRulesForFormat(apiFormat: string, force = false): Promise<BodyRule[]> {
   if (!apiFormat) return []
   const providerType = (props.provider?.provider_type || '').toLowerCase()
-  // 缓存 key 需要包含 provider_type，不同类型的 provider 有不同的默认规则
-  const cacheKey = providerType ? `${apiFormat}:${providerType}` : apiFormat
+  const cacheKey = defaultBodyRulesCacheKey(apiFormat)
   if (!force && defaultBodyRulesLoaded.value[cacheKey]) {
     return defaultBodyRulesByFormat.value[cacheKey] || []
   }
@@ -2222,7 +2232,7 @@ watch(() => props.endpoints, (endpoints) => {
       }
     }
     const newFormats = localEndpoints.value
-      .filter(e => e.api_format && !defaultBodyRulesLoaded.value[e.api_format])
+      .filter(e => e.api_format && !defaultBodyRulesLoaded.value[defaultBodyRulesCacheKey(e.api_format)])
       .map(e => ({ api_format: e.api_format }) as ProviderEndpoint)
     if (newFormats.length) {
       void preloadDefaultBodyRules(newFormats)

frontend/src/features/providers/components/provider-tabs/ModelTestDialog.vue

@@ -499,7 +499,7 @@
         v-else-if="!showTraceTimeline"
         class="py-4 text-center text-sm text-muted-foreground"
       >
-        没有可用的候选进行测试
+        {{ resultEmptyMessage }}
       </div>
 
       <div
@@ -734,19 +734,33 @@ const dialogDescription = computed(() => {
   return ''
 })
 
+const resultAttempts = computed(() => props.result?.attempts ?? [])
+
 const hasEffectiveModel = computed(() => {
   if (!props.result) return false
-  return props.result.attempts.some(attempt => attempt.effective_model && attempt.effective_model !== props.result?.model)
+  return resultAttempts.value.some(
+    attempt => attempt.effective_model && attempt.effective_model !== props.result?.model,
+  )
 })
 
 const showEndpointColumn = computed(() => {
   if (!props.result) return false
   if (props.mode === 'direct') return true
-  const formats = new Set(props.result.attempts.map(attempt => attempt.endpoint_api_format))
+  const formats = new Set(resultAttempts.value.map(attempt => attempt.endpoint_api_format))
   return formats.size > 1
 })
 
-const resultAttempts = computed(() => props.result?.attempts ?? [])
+const resultEmptyMessage = computed(() => {
+  if (!props.result) return '没有可用的候选进行测试'
+  if (typeof props.result.error === 'string' && props.result.error.trim()) {
+    return props.result.error.trim()
+  }
+  const rawResult = props.result as TestModelFailoverResponse & { message?: string }
+  if (typeof rawResult.message === 'string' && rawResult.message.trim()) {
+    return rawResult.message.trim()
+  }
+  return '没有可用的候选进行测试'
+})
 const showAllAttempts = ref(false)
 const inspectionTab = ref<'request-headers' | 'request-body' | 'response-headers' | 'response-body'>('request-body')
 const selectedInspectionKey = ref<string | null>(null)

frontend/src/features/usage/components/RequestDetailDrawer.vue

@@ -103,7 +103,10 @@
             >
               <span class="flex items-center gap-1">
                 <span class="font-medium text-foreground">ID:</span>
-                <span class="font-mono">{{ detail.request_id || detail.id }}</span>
+                <span
+                  class="font-mono"
+                  :title="fullRequestId"
+                >{{ displayRequestId }}</span>
               </span>
               <span class="opacity-40">|</span>
               <span>{{ formatDateTime(detail.created_at) }}</span>
@@ -698,6 +701,7 @@ import TabsContent from '@/components/ui/tabs-content.vue'
 import { Copy, Check, Maximize2, Minimize2, Columns2, RefreshCw, X, Monitor, Server, MessageSquareText, Code2, Terminal, Play } from 'lucide-vue-next'
 import { dashboardApi, type RequestDetail } from '@/api/dashboard'
 import { formatApiFormat } from '@/api/endpoints/types/api-format'
+import { formatShortRequestId } from '@/utils/format'
 import { log } from '@/utils/logger'
 
 // 子组件
@@ -770,6 +774,9 @@ let bodyLoadRequestId = 0
 let loadDetailInFlight = false
 let timelineMountTimer: ReturnType<typeof setTimeout> | null = null
 
+const fullRequestId = computed(() => detail.value?.request_id || detail.value?.id || '-')
+const displayRequestId = computed(() => formatShortRequestId(fullRequestId.value))
+
 // 监听标签页切换
 watch(activeTab, (newTab) => {
   if (!['request-headers', 'response-headers'].includes(newTab) && viewMode.value === 'compare') {