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.

lib/Service/BackupService.php

@@ -225,6 +225,9 @@ final class BackupService {
 			} else {
 				$state['files']['estimate'] ??= $this->estimateBytes($run, $state['files']);
 				$state['files'] = BackupRun::step($repo, $state['files'], $deadline);
+				if (in_array($state['files']['phase'], ['finish', 'commit'], true)) {
+					$run->setPhase('commit'); // all files read: writing and recording the snapshot
+				}
 				if ($state['files']['phase'] === 'commit') {
 					// Catalog write under the catalog lock, from a repository opened inside it: a per-user
 					// export or restore may have written the catalog since this step opened $repo.