add backup retention and cinfigure 7 days in compose

backup.sh

@@ -4,9 +4,14 @@ set -e
 
 NOW=$(date +"%Y%m%d-%H%M")
 OUT="/backup/output/gitea-$NOW.tar.gz"
+KEEP_FILES=${KEEP_FILES:-4}
 
 echo "== Gitea SQLite Backup $NOW =="
 
 tar -czvf "$OUT" /data/gitea
 
 echo "Backup saved as $OUT"
+
+echo "== Cleanup: keeping last $KEEP_FILES backups =="
+ls -1t /backup/output/gitea-*.tar.gz 2>/dev/null | tail -n +$((KEEP_FILES + 1)) | xargs -r rm -f
+#echo "Cleanup done."