Fix cleanup routine to reset state each cycle and skip removing upload root

main.go

@@ -395,6 +395,9 @@ func cleanupProcedure(duration time.Duration, dryRun bool) {
 		if !d.IsDir() {
 			return nil
 		}
+		if filepath.Clean(path) == filepath.Clean(uploadDir) {
+			return nil
+		}
 		empty, err := isDirEmpty(path)
 		if empty {
 			emptyDirs = append(emptyDirs, path)
@@ -406,6 +409,8 @@ func cleanupProcedure(duration time.Duration, dryRun bool) {
 	}
 
 	for {
+		oldFiles = oldFiles[:0]
+		emptyDirs = emptyDirs[:0]
 
 		filepath.WalkDir(uploadDir, deleteIfTooOld)
 		for _, file := range oldFiles {