Review fixes: a missed passphrase change follows at the next backup, a key from before 1.1.0 counts as used, schedules edited in their own time zone

- A location that a passphrase change could not reach gets it at its next backup
- A key from before 1.1.0 is never replaced as an unused one
- An unreadable settings file on a location is told apart from a missing one
- A schedule is shown and saved in the zone it was saved in
- Saving an unchanged schedule keeps its moment; --timezone needs a schedule
- Schedule coverage uses the time the backup began reading its data
- Tests: catch-up scenario, upgrade test restores the new file, autumn clock change

lib/Command/TargetAdd.php

@@ -161,9 +161,12 @@ HELP);
 			$r['target']->getRepositoryId(), $r['created'] ? 'created' : 'found and adopted'));
 		if ($passphrase !== null) {
 			$output->writeln(($replace ? 'The unused key was replaced. ' : '') . 'Backup key taken from the location, fingerprint <info>' . $this->keys->fingerprint() . '</info>.');
-			$output->writeln(array_key_exists('deleteDelayDays', $r) && $r['deleteDelayDays'] !== null
-				? 'Deletion delay for forgotten snapshots: <info>' . $this->keys->deleteDelayDays() . '</info> days (from the location).'
-				: 'Deletion delay for forgotten snapshots: <info>' . $this->keys->deleteDelayDays() . '</info> days (the default: the location has none stored, its backups were made before NG Backup 1.1.0).');
+			$days = 'Deletion delay for forgotten snapshots: <info>' . $this->keys->deleteDelayDays() . '</info> days';
+			$output->writeln(match (true) {
+				($r['deleteDelayDays'] ?? null) !== null => $days . ' (from the location).',
+				$r['settingsUnreadable'] ?? false => '<comment>' . $days . ' (the default: the settings file on the location could not be read, it may be damaged). If this server used a longer delay, removed restore points leave the Bin sooner than before.</comment>',
+				default => $days . ' (the default: the location has none stored, its backups were made before NG Backup 1.1.0).',
+			});
 			$output->writeln('Next: <info>occ backup:list</info> and <info>occ backup:restore:full</info>. Before backups run again, download a new recovery kit and confirm it (<info>occ backup:key:kit</info>, <info>occ backup:key:confirm</info>).');
 		}
 		return 0;