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/features/usage/composables/useUsageData.ts

@@ -731,7 +731,13 @@ export function useUsageData(options: UseUsageDataOptions) {
           ? (typeof record.actual_service_tier === 'string' && record.actual_service_tier.trim()
               ? record.actual_service_tier
               : null)
-          : existing.actual_service_tier
+          : existing.actual_service_tier,
+        // 终态列表快照是最终候选的权威事实；空值必须清除旧候选的响应模型。
+        response_model: statusProgressed
+          ? (typeof record.response_model === 'string' && record.response_model.trim()
+              ? record.response_model
+              : null)
+          : existing.response_model
       }
     })
   }

frontend/src/features/usage/composables/useUsageFilters.ts

@@ -3,6 +3,7 @@ import type { UsageRecord, FilterStatusValue } from '../types'
 import {
   hasUsageFallback,
   hasUsageRetry,
+  hasUsageSkippedCandidate,
   isUsageRecordFailed,
   isUsageUpstreamStream,
   isUsageWebSocket,
@@ -97,6 +98,8 @@ export function useUsageFilters(options: UseUsageFiltersOptions) {
         records = records.filter(record => hasUsageFallback(record))
       } else if (filterStatus.value === 'has_retry') {
         records = records.filter(record => hasUsageRetry(record))
+      } else if (filterStatus.value === 'has_skipped_candidate') {
+        records = records.filter(record => hasUsageSkippedCandidate(record))
       }
     }