test: add unit tests generated by ToTheos

jest.config.js

@@ -0,0 +1,32 @@
+/** @type {import("jest").Config} **/
+module.exports = {
+  testEnvironment: "jsdom",
+  setupFilesAfterEnv: ["<rootDir>/src/setupTests.js"],
+  extensionsToTreatAsEsm: ['.ts'],
+  preset: 'ts-jest/presets/default-esm',
+  transform: {
+    "^.+\\.tsx?$": [
+      "ts-jest",
+      {
+        "useESM": true,
+        "tsconfig": {
+          "module": "esnext",
+          "target": "es2020",
+          "esModuleInterop": true,
+          "allowSyntheticDefaultImports": true,
+          "strict": false,
+          "moduleResolution": "node"
+        }
+      }
+    ]
+  },
+  testMatch: ["**/*.test.ts", "**/*.test.tsx"],
+  moduleNameMapper: {
+    '^(\\.{1,2}/.*)\\.js$': '$1',
+    '^src/(.*)$': '<rootDir>/src/$1',
+  },
+  "bail": 1,
+  "modulePathIgnorePatterns": ["<rootDir>/node_modules", "<rootDir>/dist"],
+  "resetMocks": true,
+  "testPathIgnorePatterns": ["/node_modules/", "/__mocks__/"]
+};