Fall back to host tar when container is down

When the minecraft container is not running, archive data/world
directly from the host instead of failing — the files are already
consistent on disk with no process writing to them.

backup.sh

@@ -1,7 +1,8 @@
 #!/usr/bin/env bash
 # Usage: ./backup.sh [label]
 # Creates backups/world-YYYY-MM-DD-HHMM[-label].tar.gz
-# Requires the minecraft container to be running.
+# If the container is running, flushes world via rcon and archives via
+# docker exec. If not, archives data/world from the host directly.
 set -euo pipefail
 
 cd "$(dirname "$0")"
@@ -13,18 +14,18 @@ OUT="backups/world-${STAMP}${SUFFIX}.tar.gz"
 
 mkdir -p backups
 
-if ! docker ps --format '{{.Names}}' | grep -qx minecraft; then
-    echo "Error: minecraft container is not running." >&2
-    exit 1
-fi
-
-echo "Flushing world via rcon..."
+if docker ps --format '{{.Names}}' | grep -qx minecraft; then
+    echo "Server running — flushing world via rcon..."
     docker exec minecraft rcon-cli save-off >/dev/null
     docker exec minecraft rcon-cli save-all flush >/dev/null
     trap 'docker exec minecraft rcon-cli save-on >/dev/null || true' EXIT
 
     echo "Archiving /data/world -> ${OUT}"
     docker exec minecraft tar -czf - -C /data world > "${OUT}"
+else
+    echo "Server not running — archiving data/world from host."
+    tar -czf "${OUT}" -C data world
+fi
 
 echo "Done."
 ls -lh "${OUT}"