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/sensors.ts

@@ -32,24 +32,45 @@ export async function fetchHistory(id: string, src?: Source): Promise<{ t: numbe
   return r.ok ? r.json() : null
 }
 
-// useSensorStream keeps a shaped query answered: the object comes back filled with whole
-// sensors and is replaced on every sample. One stream serves any number of widgets.
-export function useSensorStream<T = unknown>(shape: Shape | null, src?: Source, everyMs?: number): { data: T | null; error: string } {
+export async function fetchHistories(ids: string, src?: Source): Promise<{ id: string; unit?: string; t: number[]; v: number[] }[]> {
+  const r = await fetch(url(src, '/api/sensors/history', { ids }), { credentials: 'same-origin' })
+  if (!r.ok) throw new Error(r.statusText)
+  return (await r.json()).series
+}
+
+export interface StreamOpts { src?: Source; everyMs?: number; full?: boolean }
+
+// useSensorStream keeps a shaped query answered: the object comes back filled (with whole
+// sensors unless full is false) and is replaced on every sample. One stream serves any
+// number of widgets. It closes while the page is hidden — a phone in a pocket shouldn't
+// hold a stream open — and `resumed` counts the times it came back, so a caller that
+// keeps history knows there is a gap to refill.
+export function useSensorStream<T = unknown>(shape: Shape | null, opts: StreamOpts = {}): { data: T | null; error: string; resumed: number } {
   const [data, setData] = useState<T | null>(null)
   const [error, setError] = useState('')
+  const [resumed, setResumed] = useState(0)
+  const [visible, setVisible] = useState(() => document.visibilityState === 'visible')
   const key = shape === null ? '' : JSON.stringify(shape)
-  const srcKey = `${src?.machine ?? '·'}|${src?.token ?? ''}|${everyMs ?? ''}`
+  const { src, everyMs, full = true } = opts
+  const srcKey = `${src?.machine ?? '·'}|${src?.token ?? ''}|${everyMs ?? ''}|${full}`
   const srcRef = useRef(src); srcRef.current = src
+  useEffect(() => {
+    const onVis = () => { const v = document.visibilityState === 'visible'; setVisible(v); if (v) setResumed((n) => n + 1) }
+    document.addEventListener('visibilitychange', onVis)
+    return () => document.removeEventListener('visibilitychange', onVis)
+  }, [])
   useEffect(() => {
     if (!key) { setData(null); return }
-    const params: Record<string, string> = { q: key, full: '1' }
+    if (!visible) return
+    const params: Record<string, string> = { q: key }
+    if (full) params.full = '1'
     if (everyMs) params.every = String(everyMs)
     const es = new EventSource(url(srcRef.current, '/api/sensors/stream', params))
     es.onmessage = (e) => { try { setData(JSON.parse(e.data)); setError('') } catch { /* skip a bad frame */ } }
     es.onerror = () => setError('reconnecting…') // EventSource retries by itself
     return () => es.close()
-  }, [key, srcKey]) // eslint-disable-line react-hooks/exhaustive-deps
-  return { data, error }
+  }, [key, srcKey, visible]) // eslint-disable-line react-hooks/exhaustive-deps
+  return { data, error, resumed }
 }
 
 // ---- formatting, by unit ----