automatically calculate base combat values

src/module/settings.ts

@@ -0,0 +1,12 @@
+export function registerSystemSettings(): void {
+    /**
+     * Track the system version upon which point a migration was last applied
+     */
+    game.settings.register("ds4", "systemMigrationVersion", {
+        name: "System Migration Version",
+        scope: "world",
+        config: false,
+        type: String,
+        default: "",
+    });
+}