refactor(ui): server metrics page uses global time range

Drop the page-local DS Select window picker. Drive from() / to() off
useGlobalFilters().timeRange so the dashboard tracks the same TopBar range
as Exchanges / Dashboard / Runtime. Bucket size auto-scales via
stepSecondsFor(windowSeconds) (10 s for ≤30 min → 1 h for >48 h). Query
hooks now take ServerMetricsRange = { from: Date; to: Date } instead of a
windowSeconds number, so they support arbitrary absolute or rolling ranges
the TopBar may supply (not just "now − N"). Toolbar collapses to just the
server-instance badges.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

.claude/rules/ui.md

@@ -21,7 +21,7 @@ The UI has 4 main tabs: **Exchanges**, **Dashboard**, **Runtime**, **Deployments
 
 **Admin pages** (ADMIN-only, under `/admin/`):
 - **Sensitive Keys** (`ui/src/pages/Admin/SensitiveKeysPage.tsx`) — global sensitive key masking config. Shows agent built-in defaults as outlined Badge reference, editable Tag pills for custom keys, amber-highlighted push-to-agents toggle. Keys add to (not replace) agent defaults. Per-app sensitive key additions managed via `ApplicationConfigController` API. Note: `AppConfigDetailPage.tsx` exists but is not routed in `router.tsx`.
-- **Server Metrics** (`ui/src/pages/Admin/ServerMetricsAdminPage.tsx`) — dashboard over the `server_metrics` ClickHouse table. Visibility matches Database/ClickHouse pages: gated on `capabilities.infrastructureEndpoints` in `buildAdminTreeNodes`; backend is `@ConditionalOnProperty(infrastructureendpoints) + @PreAuthorize('hasRole(ADMIN)')`. Uses the generic `/api/v1/admin/server-metrics/{catalog,instances,query}` API via `ui/src/api/queries/admin/serverMetrics.ts` hooks (`useServerMetricsCatalog`, `useServerMetricsInstances`, `useServerMetricsSeries`). Toolbar: server-instance badges + DS `Select` window picker (15 min / 1 h / 6 h / 24 h / 7 d). Sections: Server health (agents/ingestion/auth), JVM (memory/CPU/GC/threads), HTTP & DB pools, Alerting (conditional on catalog), Deployments (conditional on catalog). Each panel is a `ThemedChart` with `Line`/`Area` children from the design system; multi-series responses are flattened into overlap rows by bucket timestamp. Alerting and Deployments rows are hidden when their metrics aren't in the catalog (zero-deploy / alerting-disabled installs).
+- **Server Metrics** (`ui/src/pages/Admin/ServerMetricsAdminPage.tsx`) — dashboard over the `server_metrics` ClickHouse table. Visibility matches Database/ClickHouse pages: gated on `capabilities.infrastructureEndpoints` in `buildAdminTreeNodes`; backend is `@ConditionalOnProperty(infrastructureendpoints) + @PreAuthorize('hasRole(ADMIN)')`. Uses the generic `/api/v1/admin/server-metrics/{catalog,instances,query}` API via `ui/src/api/queries/admin/serverMetrics.ts` hooks (`useServerMetricsCatalog`, `useServerMetricsInstances`, `useServerMetricsSeries`), all three of which take a `ServerMetricsRange = { from: Date; to: Date }`. Time range is driven by the global TopBar picker via `useGlobalFilters()` — no page-local selector; bucket size auto-scales through `stepSecondsFor(windowSeconds)` (10 s up to 1 h buckets). Toolbar is just server-instance badges. Sections: Server health (agents/ingestion/auth), JVM (memory/CPU/GC/threads), HTTP & DB pools, Alerting (conditional on catalog), Deployments (conditional on catalog). Each panel is a `ThemedChart` with `Line`/`Area` children from the design system; multi-series responses are flattened into overlap rows by bucket timestamp. Alerting and Deployments rows are hidden when their metrics aren't in the catalog (zero-deploy / alerting-disabled installs).
 
 ## Key UI Files