Fast S3 verify and snapshot commit; shorter runs list; durations with days

On S3, index files and the tree segments read back when a snapshot is
written are fetched 16 at a time through the storage's S3 client
(IBackend::getRanges(), getMany()). Blobs that follow each other in a pack
are read as one range on every location. The snapshot is written in a step
of its own and the run shows "commit" meanwhile. On a 1 TB production
repository the check went from about 4 hours to 3.5 minutes.

backup:status and the web interface list the runs of the last 7 days,
running ones and at least the newest 5; --all / "Show older runs" list
all. Durations of a day or more show the days.

src/AdminSettings.vue

@@ -22,7 +22,7 @@
 			</template>
 			<template v-else-if="status.key.everConfirmed">
 				<template v-if="status.targets.length">
-					<Backups :status="status" @changed="refresh" />
+					<Backups :status="status" :all-runs="allRuns" @changed="refresh" @show-all-runs="showAllRuns" />
 					<RestoreBrowser :status="status" @changed="refresh" />
 				</template>
 				<NcNoteCard v-else type="info">{{ t('ng_backup', 'Add a backup location under "Settings" first.') }}</NcNoteCard>
@@ -46,14 +46,20 @@ import Locations from './components/Locations.vue'
 import RestoreBrowser from './components/RestoreBrowser.vue'
 
 const status = ref(null)
+const allRuns = ref(false) // runs older than the last days too
 const error = ref('')
 const tab = ref('settings')
 let tabInitialized = false
 let timer = null
 
+function showAllRuns(all) {
+	allRuns.value = all
+	refresh()
+}
+
 async function refresh() {
 	try {
-		status.value = await api.status()
+		status.value = await api.status(allRuns.value)
 		error.value = ''
 		// Default to the daily-use tab once the key is set up; stay on Settings otherwise.
 		// Only decided on first load, so switching tabs ourselves isn't undone by polling.