Merge upstream/main into feat/grok-complete-integration

冲突集中在 chat completions / messages 两条 Responses 转发路径：
upstream 给 OpenAIForwardResult 增加了 UpstreamResponseModel 与
UpstreamResponseModelConflict（配套 beginUpstreamResponseModelObservation
观测器），本分支在同样位置把返回值改成了具名变量以便挂 Grok 原生搜索计数。
两侧不互斥，合并结果同时保留上游的响应模型观测字段与 Grok SearchCount 逻辑。

frontend/pnpm-lock.yaml 取 upstream 版本：package.json 与 upstream 完全一致，
本地差异只是 pnpm install 的重解析噪音。

frontend/src/views/admin/UsageView.vue

@@ -450,6 +450,7 @@ const loadModelStats = async (source: ModelDistributionSource, force = false) =>
       request_type: requestType,
       stream: legacyStream === null ? undefined : legacyStream,
       billing_type: filters.value.billing_type,
+	  upstream_model_mismatch: filters.value.upstream_model_mismatch,
     }
 
     const response = await adminAPI.dashboard.getModelStats({ ...baseParams, model_source: source })
@@ -499,6 +500,7 @@ const loadChartData = async () => {
       request_type: requestType,
       stream: legacyStream === null ? undefined : legacyStream,
       billing_type: filters.value.billing_type,
+	  upstream_model_mismatch: filters.value.upstream_model_mismatch,
       include_stats: false,
       include_trend: true,
       include_model_stats: false,
@@ -573,7 +575,7 @@ const exportToExcel = async () => {
     const XLSX = await import('xlsx')
     const headers = [
       t('usage.time'), t('admin.usage.user'), t('usage.apiKeyFilter'),
-      t('admin.usage.account'), t('usage.model'), t('usage.upstreamModel'), t('usage.reasoningEffort'), t('admin.usage.group'),
+      t('admin.usage.account'), t('usage.requestedModel'), t('usage.sentUpstreamModel'), t('usage.upstreamResponseModel'), t('usage.upstreamModelMismatch'), t('usage.reasoningEffort'), t('admin.usage.group'),
       t('usage.inboundEndpoint'), t('usage.upstreamEndpoint'),
       t('usage.type'),
       t('admin.usage.inputTokens'), t('admin.usage.outputTokens'),
@@ -593,7 +595,7 @@ const exportToExcel = async () => {
       if (c.signal.aborted) break; if (p === 1) { total = res.total; exportProgress.total = total }
       const rows = (res.items || []).map((log: AdminUsageLog) => [
         log.created_at, log.user?.email || '', log.api_key?.name || '', log.account?.name || '', log.model,
-        log.upstream_model || '', formatReasoningEffort(log.reasoning_effort), log.group?.name || '',
+        log.upstream_model || log.model, log.upstream_response_model || '', log.upstream_model_mismatch == null ? '' : t(log.upstream_model_mismatch ? 'common.yes' : 'common.no'), formatReasoningEffort(log.reasoning_effort), log.group?.name || '',
         log.inbound_endpoint || '', log.upstream_endpoint || '', getRequestTypeLabel(log),
         log.input_tokens, log.output_tokens, log.cache_read_tokens, log.cache_creation_tokens,
         log.input_cost?.toFixed(6) || '0.000000', log.output_cost?.toFixed(6) || '0.000000',

frontend/src/views/admin/__tests__/UsageView.spec.ts

@@ -4,7 +4,7 @@ import { defineComponent, ref } from 'vue'
 
 import UsageView from '../UsageView.vue'
 
-const { list, getStats, getSnapshotV2, getById, getModelStats, listErrorLogs, routeQuery } = vi.hoisted(() => {
+const { list, exportList, getStats, getSnapshotV2, getById, getModelStats, listErrorLogs, routeQuery, aoaToSheet, sheetAddAoa, saveAs, xlsxWrite } = vi.hoisted(() => {
   vi.stubGlobal('localStorage', {
     getItem: vi.fn(() => null),
     setItem: vi.fn(),
@@ -13,12 +13,17 @@ const { list, getStats, getSnapshotV2, getById, getModelStats, listErrorLogs, ro
 
   return {
     list: vi.fn(),
+		exportList: vi.fn(),
     getStats: vi.fn(),
     getSnapshotV2: vi.fn(),
     getById: vi.fn(),
     getModelStats: vi.fn(),
     listErrorLogs: vi.fn(),
     routeQuery: {} as Record<string, string>,
+		aoaToSheet: vi.fn(() => ({})),
+		sheetAddAoa: vi.fn(),
+		saveAs: vi.fn(),
+		xlsxWrite: vi.fn(() => new Uint8Array([1, 2, 3])),
   }
 })
 
@@ -27,6 +32,12 @@ const messages: Record<string, string> = {
   'admin.dashboard.day': 'Day',
   'admin.dashboard.hour': 'Hour',
   'admin.usage.failedToLoadUser': 'Failed to load user',
+	'usage.requestedModel': 'Requested model',
+	'usage.sentUpstreamModel': 'Sent upstream model',
+	'usage.upstreamResponseModel': 'Upstream response model',
+	'usage.upstreamModelMismatch': 'Upstream model mismatch',
+	'common.yes': 'Yes',
+	'common.no': 'No',
 }
 
 const formatLocalDate = (date: Date): string => {
@@ -54,10 +65,22 @@ vi.mock('@/api/admin', () => ({
 
 vi.mock('@/api/admin/usage', () => ({
   adminUsageAPI: {
-    list: vi.fn(),
+		list: exportList,
   },
 }))
 
+vi.mock('file-saver', () => ({ saveAs }))
+
+vi.mock('xlsx', () => ({
+	utils: {
+		aoa_to_sheet: aoaToSheet,
+		sheet_add_aoa: sheetAddAoa,
+		book_new: vi.fn(() => ({})),
+		book_append_sheet: vi.fn(),
+	},
+	write: xlsxWrite,
+}))
+
 vi.mock('@/api/admin/ops', () => ({
   listErrorLogs,
 }))
@@ -539,3 +562,62 @@ describe('admin UsageView ranking tab', () => {
     expect(list).toHaveBeenCalledWith(expect.objectContaining({ user_id: 5 }), expect.anything())
   })
 })
+
+describe('admin UsageView model audit export', () => {
+	beforeEach(() => {
+		vi.useFakeTimers()
+		list.mockReset().mockResolvedValue({ items: [], total: 0, pages: 0 })
+		exportList.mockReset().mockResolvedValue({
+			items: [{
+				id: 1,
+				created_at: '2026-08-04T00:00:00Z',
+				model: 'gpt-5.6-sol',
+				upstream_model: 'gpt-5.5',
+				upstream_response_model: 'gpt-5.4',
+				upstream_model_mismatch: true,
+				request_type: 'sync',
+				input_tokens: 1,
+				output_tokens: 1,
+				cache_read_tokens: 0,
+				cache_creation_tokens: 0,
+				duration_ms: 10,
+			}],
+			total: 1,
+			pages: 1,
+		})
+		getStats.mockReset().mockResolvedValue({
+			total_requests: 0, total_input_tokens: 0, total_output_tokens: 0,
+			total_cache_tokens: 0, total_tokens: 0, total_cost: 0, total_actual_cost: 0, average_duration_ms: 0,
+		})
+		getSnapshotV2.mockReset().mockResolvedValue({ trend: [], models: [], groups: [] })
+		getModelStats.mockReset().mockResolvedValue({ models: [] })
+		aoaToSheet.mockClear()
+		sheetAddAoa.mockClear()
+		saveAs.mockClear()
+		xlsxWrite.mockClear()
+	})
+
+	afterEach(() => {
+		vi.useRealTimers()
+	})
+
+	it('exports requested, sent, response, and mismatch as separate admin columns', async () => {
+		const wrapper = mountRouteFilteredUsageView()
+		vi.advanceTimersByTime(120)
+		await flushPromises()
+
+		await (wrapper.vm as any).exportToExcel()
+		await flushPromises()
+
+		const headers = aoaToSheet.mock.calls[0][0][0]
+		expect(headers.slice(4, 8)).toEqual([
+			'Requested model',
+			'Sent upstream model',
+			'Upstream response model',
+			'Upstream model mismatch',
+		])
+		const row = sheetAddAoa.mock.calls[0][1][0]
+		expect(row.slice(4, 8)).toEqual(['gpt-5.6-sol', 'gpt-5.5', 'gpt-5.4', 'Yes'])
+		expect(saveAs).toHaveBeenCalledTimes(1)
+	})
+})

frontend/src/views/admin/ops/OpsDashboard.vue

@@ -114,6 +114,8 @@
         <OpsErrorDetailsModal
           :show="showErrorDetails"
           :time-range="timeRange"
+          :custom-start-time="customStartTime"
+          :custom-end-time="customEndTime"
           :platform="platform"
           :group-id="groupId"
           :error-type="errorDetailsType"

frontend/src/views/admin/ops/components/OpsErrorDetailsModal.vue

@@ -5,10 +5,13 @@ import BaseDialog from '@/components/common/BaseDialog.vue'
 import Select from '@/components/common/Select.vue'
 import OpsErrorLogTable from './OpsErrorLogTable.vue'
 import { opsAPI, type OpsErrorLog } from '@/api/admin/ops'
+import { buildOpsErrorTimeParams } from '../utils/opsErrorParams'
 
 interface Props {
   show: boolean
   timeRange: string
+  customStartTime?: string | null
+  customEndTime?: string | null
   platform?: string
   groupId?: number | null
   errorType: 'request' | 'upstream'
@@ -103,11 +106,11 @@ async function fetchErrorLogs() {
     const params: Record<string, any> = {
       page: page.value,
       page_size: pageSize.value,
-      time_range: props.timeRange,
       view: viewMode.value,
       sort_by: sortBy.value,
       sort_order: sortOrder.value
     }
+    Object.assign(params, buildOpsErrorTimeParams(props.timeRange, props.customStartTime, props.customEndTime))
 
     const platform = String(props.platform || '').trim()
     if (platform) params.platform = platform
@@ -160,7 +163,7 @@ watch(
 )
 
 watch(
-  () => [props.timeRange, props.platform, props.groupId] as const,
+  () => [props.timeRange, props.customStartTime, props.customEndTime, props.platform, props.groupId] as const,
   () => {
     if (!props.show) return
     page.value = 1

frontend/src/views/admin/ops/utils/__tests__/opsErrorParams.spec.ts

@@ -0,0 +1,16 @@
+import { describe, expect, it } from 'vitest'
+import { buildOpsErrorTimeParams } from '../opsErrorParams'
+
+describe('buildOpsErrorTimeParams', () => {
+  it('uses explicit timestamps for a complete custom range', () => {
+    expect(buildOpsErrorTimeParams('custom', '2026-08-01T00:00:00Z', '2026-08-02T00:00:00Z')).toEqual({
+      start_time: '2026-08-01T00:00:00Z',
+      end_time: '2026-08-02T00:00:00Z'
+    })
+  })
+
+  it('preserves predefined ranges and falls back for incomplete custom ranges', () => {
+    expect(buildOpsErrorTimeParams('24h')).toEqual({ time_range: '24h' })
+    expect(buildOpsErrorTimeParams('custom', null, null)).toEqual({ time_range: '1h' })
+  })
+})

frontend/src/views/admin/ops/utils/opsErrorParams.ts

@@ -0,0 +1,11 @@
+export function buildOpsErrorTimeParams(
+  timeRange: string,
+  customStartTime?: string | null,
+  customEndTime?: string | null
+): Record<string, string> {
+  if (timeRange === 'custom' && customStartTime && customEndTime) {
+    return { start_time: customStartTime, end_time: customEndTime }
+  }
+
+  return { time_range: timeRange === 'custom' ? '1h' : timeRange }
+}