test: setup Jest configuration and add initial test

- Renamed jest.config.js to jest.config.cjs to fix ES modules compatibility
- Added a basic test file to verify Jest setup

Author: anton-107

jest.config.js renamed to jest.config.cjs

@@ -0,0 +1,5 @@
+describe("Main module", () => {
+  it("should pass a simple test", () => {
+    expect(true).toBe(true);
+  });
+});