1.0.1: label for "Back up now", retention explained in the trash, occ times in the schedule's zone, single-file restore to a directory, leftovers of a stopped restore removed

- Admin page: an optional label (at most 100 characters) for a backup started with "Back up now";
  an (i) by "removed by retention policy" in the trash that explains what it means and until when
  the restore point can be brought back. backup:trash says the same below its list.
- backup:status, backup:list, backup:trash and backup:browse show times in the zone of the daily
  schedule and name it, instead of the server's UTC.
- backup:restore --to-directory of a file restored nothing: the path got a "/" appended.
- A restore removes "<name>.ngb-restore-<hex>" temporaries that a stopped restore left in the
  folders it writes to.
- Roadmap: the cron warning (#13), reading ahead from S3/SMB and --salvage move to 1.0.2.

lib/Format.php

@@ -15,4 +15,14 @@ final class Format {
 		$time = gmdate('H:i:s', $seconds % 86400);
 		return $days > 0 ? $days . 'd ' . $time : $time;
 	}
+
+	/**
+	 * "2026-10-29 04:30" in $zone. Nextcloud runs PHP in UTC; occ shows times in the zone of the
+	 * schedule, the administrator's, as the web interface does.
+	 *
+	 * @param non-empty-string $zone
+	 */
+	public static function time(int $timestamp, string $zone): string {
+		return (new \DateTimeImmutable('@' . $timestamp))->setTimezone(new \DateTimeZone($zone))->format('Y-m-d H:i');
+	}
 }