add pxl8.get_title() API to expose cart title to Lua

pxl8.sh

@@ -406,17 +406,21 @@ case "$COMMAND" in
         "$0" build "$@" || exit 1
 
         CART=""
+        EXTRA_ARGS=""
         for arg in "$@"; do
-            if [[ "$arg" != "--release" ]]; then
+            if [[ "$arg" == "--release" ]]; then
+                continue
+            elif [[ "$arg" == "--repl" ]]; then
+                EXTRA_ARGS="$EXTRA_ARGS --repl"
+            elif [[ -z "$CART" ]]; then
                 CART="$arg"
-                break
             fi
         done
 
         if [[ -z "$CART" ]]; then
-            "$BINDIR/pxl8"
+            "$BINDIR/pxl8" $EXTRA_ARGS
         else
-            "$BINDIR/pxl8" "$CART"
+            "$BINDIR/pxl8" "$CART" $EXTRA_ARGS
         fi
         ;;