M2: full backup runs (database, config, data) with occ and cron

BackupService starts a run per location (database dump in one
transaction, then config + data directory as a resumable file run),
stores the state in ngb_runs after every step, locks a run while a step
executes and records the snapshot. Previews, logs, updater backups and
per-user cache/uploads are excluded (TreeWalker now supports patterns).
BackupJob (every 5 min) starts the daily schedule and steps running runs
with a short budget under web cron and a long one under system cron.
occ: backup:run, backup:status, backup:list.

Tested on NC34/PostgreSQL: first run 128 files / 1 GiB in 64 s (443 MiB
uploaded to S3), unchanged second run 2 s / 0 bytes; a background run to
SFTP completed through cron.php.

lib/Job/TreeWalker.php

@@ -17,7 +17,8 @@ namespace OCA\NgBackup\Job;
 final class TreeWalker {
 	/**
 	 * @param array<string, string> $roots name => absolute directory, walked in this order
-	 * @param list<string> $exclude path prefixes ("<root>/<relative>") that are skipped entirely
+	 * @param list<string> $exclude path prefixes ("<root>/<relative>") that are skipped entirely;
+	 *                              a pattern with "*" matches one path segment (fnmatch, FNM_PATHNAME)
 	 */
 	public function __construct(
 		private array $roots,
@@ -51,10 +52,8 @@ final class TreeWalker {
 	}
 
 	private function walkDir(string $abs, string $logical, ?string $after): \Generator {
-		foreach ($this->exclude as $prefix) {
-			if ($logical !== '' && ($logical === $prefix || str_starts_with($logical, $prefix . '/'))) {
-				return;
-			}
+		if ($logical !== '' && $this->isExcluded($logical, true)) {
+			return;
 		}
 		$names = @scandir($abs);
 		if ($names === false) {
@@ -78,20 +77,26 @@ final class TreeWalker {
 				if ($after !== null && self::compare($childLogical, $after) <= 0) {
 					continue;
 				}
-				$excluded = false;
-				foreach ($this->exclude as $prefix) {
-					if ($childLogical === $prefix) {
-						$excluded = true;
-						break;
-					}
-				}
-				if (!$excluded) {
+				if (!$this->isExcluded($childLogical, false)) {
 					yield $childLogical => $childAbs;
 				}
 			}
 		}
 	}
 
+	private function isExcluded(string $logical, bool $isDir): bool {
+		foreach ($this->exclude as $pattern) {
+			if (str_contains($pattern, '*')) {
+				if (fnmatch($pattern, $logical, FNM_PATHNAME)) {
+					return true;
+				}
+			} elseif ($logical === $pattern || ($isDir && str_starts_with($logical, $pattern . '/'))) {
+				return true;
+			}
+		}
+		return false;
+	}
+
 	private static function isPrefix(string $dir, string $path): bool {
 		return str_starts_with($path, $dir . '/');
 	}