The full switch: Monitors and Disks read only the sensor API; /api/metrics retired

- stock Monitors modules fed by one sensor stream, the catalog and one batch of
  histories (GET /api/sensors/history?ids=…), through sampleAdapter.ts
- the stream closes while the page is hidden and refills its curves on return
- Disks tab live rates from the stream
- new sensors: hamlab.sample_interval, ups.last_event
- stream: asking for about the sampling rate means every sample
- NUT runtime rounded at the source

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

web/src/api.ts

@@ -168,8 +168,6 @@ export const api = {
   serviceAction: (unit: string, action: string) => req<void>('POST', `/api/services/${encodeURIComponent(unit)}/${action}`),
   dashPrefs: () => req<DashPrefs>('GET', '/api/prefs/dashboard'),
   saveDashPrefs: (p: DashPrefs) => req<void>('PUT', '/api/prefs/dashboard', p),
-  metrics: () => req<Sample>('GET', '/api/metrics'),
-  metricsHistory: () => req<Series>('GET', '/api/metrics/history'),
   login: (password: string) => req<void>('POST', '/api/login', { password }, true),
   logout: () => req<void>('POST', '/api/logout', undefined, true),
   meHere: () => req<Me>('GET', '/api/me', undefined, true),