✨ feat: Add model performance metrics to dashboard

Add a shared `performance-metrics` feature module for perf metric APIs, DTOs, and formatting, then surface global 24h model performance on the dashboard with cards and a top-model table.

Reuse the shared metrics module from pricing model details, remove duplicated perf API/formatting code from pricing, and add localized labels for the new dashboard performance UI.

web/default/src/features/pricing/api.ts

@@ -10,65 +10,3 @@ export async function getPricing(): Promise<PricingData> {
   const res = await api.get('/api/pricing')
   return res.data
 }
-
-export type PerformanceSeriesPoint = {
-  ts: number
-  avg_ttft_ms: number
-  avg_latency_ms: number
-  success_rate: number
-  avg_tps: number
-}
-
-export type PerformanceGroup = {
-  group: string
-  avg_ttft_ms: number
-  avg_latency_ms: number
-  success_rate: number
-  avg_tps: number
-  series: PerformanceSeriesPoint[]
-}
-
-export type PerformanceMetricsData = {
-  success: boolean
-  message?: string
-  data: {
-    model_name: string
-    series_schema?: string
-    groups: PerformanceGroup[]
-  }
-}
-
-export type PerfModelSummary = {
-  model_name: string
-  avg_latency_ms: number
-  success_rate: number
-  avg_tps: number
-  request_count: number
-}
-
-export type PerfSummaryAllData = {
-  success: boolean
-  message?: string
-  data: {
-    models: PerfModelSummary[]
-  }
-}
-
-export async function getPerfMetricsSummary(
-  hours = 24
-): Promise<PerfSummaryAllData> {
-  const res = await api.get(`/api/perf-metrics/summary?hours=${hours}`)
-  return res.data
-}
-
-export async function getPerfMetrics(
-  modelName: string,
-  hours = 24
-): Promise<PerformanceMetricsData> {
-  const params = new URLSearchParams({
-    model: modelName,
-    hours: String(hours),
-  })
-  const res = await api.get(`/api/perf-metrics?${params.toString()}`)
-  return res.data
-}