Merge origin/main into main

Integrate upstream updates while preserving the local analytics dashboards and schema-only migration changes.

Combine user account analysis with upstream user/group usage statistics in separate tabs, retain all migration versions, and keep the deleted audit document removed.

Validation: gateway all-target cargo check, frontend type check and 57 focused tests, 48 migration tests, schema composition checks, and diff whitespace checks.

frontend/src/views/shared/Usage.vue

@@ -527,6 +527,8 @@ const filteredRecords = computed(() => {
         records = records.filter(record => hasUsageFallback(record))
       } else if (filterStatus.value === 'has_retry') {
         records = records.filter(record => record.has_retry === true)
+      } else if (filterStatus.value === 'has_skipped_candidate') {
+        records = records.filter(record => record.has_skipped_candidate === true)
       }
     }
 
@@ -735,6 +737,10 @@ async function pollActiveRequests() {
         record.actual_service_tier = typeof update.actual_service_tier === 'string' && update.actual_service_tier.trim()
           ? update.actual_service_tier
           : null
+        // 活跃接口返回的是当前最终候选快照，服务端空值要清除旧响应模型。
+        record.response_model = typeof update.response_model === 'string' && update.response_model.trim()
+          ? update.response_model
+          : null
         // 管理员接口返回额外字段
         // 只有当返回的 provider 不是 pending/unknown/unknow 时才更新，避免覆盖已有的正确值
         if ('provider' in update && typeof update.provider === 'string') {
@@ -1307,6 +1313,7 @@ function handleDetailRequestState(update: {
   reasoningEffort?: string | null
   serviceTier?: string | null
   actualServiceTier?: string | null
+  responseModel?: string | null
   imageProgress?: ImageProgress | null
   errorMessage?: string | null
   updatedAt?: string | null
@@ -1449,6 +1456,11 @@ function handleDetailRequestState(update: {
       ? update.actualServiceTier
       : null
   }
+  if ('responseModel' in update) {
+    record.response_model = typeof update.responseModel === 'string'
+      ? update.responseModel
+      : null
+  }
   if ('imageProgress' in update) {
     const nextProgress = update.imageProgress ?? null
     if (!sameImageProgress(record.image_progress, nextProgress)) {