chore: update eslint config, update tests, constants

tests/unit/components/image/ImageManager.test.ts

@@ -1,9 +1,11 @@
 import ImageManager from "$components/image/ImageManager.svelte";
 import { render } from "@testing-library/svelte";
-import { describe, it } from "vitest";
+import { describe, expect, it } from "vitest";
 
 describe("ImageManager.svelte", () => {
   it("should render without crashing", () => {
-    render(ImageManager);
+    const { container } = render(ImageManager);
+
+    expect(container).toBeTruthy();
   });
 });