Add build archival script with timestamped snapshots (.gba, .elf, .map) (#420)

* added .sh script for copying output files under folder

* Update scripts/save_build.sh

Co-authored-by: Rickey <ric@rf3.xyz>

* Partial save functionality, comments & game name env variable

* indentation fixes

* exit with error val

Co-authored-by: Rickey <ric@rf3.xyz>

* make save_build.sh executable

---------

Co-authored-by: Rickey <ric@rf3.xyz>

scripts/save_build.sh

@@ -0,0 +1,34 @@
+#!/usr/bin/env bash
+
+# NOTE: This script is meant to be run from
+# the root repository directory to work as intended.
+
+set -e
+
+make
+
+GAME_NAME="${GAME_NAME-balatro-gba}"
+timestamp=$(date +%Y%m%d_%H%M%S)
+arg=${1:-"build"}
+dir="saved_builds/${arg}_${timestamp}"
+
+mkdir -p "$dir"
+
+failed=0
+for fe in elf gba map; do
+    if [ -f build/"$GAME_NAME".$fe ]; then
+        cp build/"$GAME_NAME".$fe "$dir/"
+    else
+        echo "Warning: build/$GAME_NAME.$fe not found"
+        failed=1
+    fi
+done
+
+if [ $failed -eq 1 ]; then
+    echo "Some files are missing, partially saved to $dir"
+else
+    echo "Build files saved to $dir"
+fi
+
+exit $failed
+