fix strength for melee weapons

src/Roster.jsx

@@ -142,7 +142,7 @@ const Unit = ({ unit, index, catalog, onePerPage }) => {
 			range: "Melee",
 			damage: "1",
 			type: "Melee",
-			str: "0",
+			str: "+0",
 			ap: "0",
 		});
 	}

src/Weapons.jsx

@@ -292,7 +292,12 @@ const getWeaponClassNames = (weapons, index) => {
 
 const calculateWeaponStrength = (strModel, strWeapon) => {
 	if (strWeapon.startsWith("User")) return strModel;
-	if (strWeapon.startsWith("x"))
+	if (strWeapon.startsWith("x")) {
 		return strModel * parseInt(strWeapon.replace("x", ""));
+	}
+	if (strWeapon.includes("+")) {
 		return strModel + parseInt(strWeapon, 10);
+	}
+	if (!strWeapon) return strModel;
+	return parseInt(strWeapon, 10);
 };