feat: login form as a client component, theme toggle

jest.config.cjs

@@ -0,0 +1,16 @@
+const nextJest = require('next/jest');
+
+const createJestConfig = nextJest({
+  dir: './',
+});
+
+const customJestConfig = {
+  setupFilesAfterEnv: ['<rootDir>/jest.setup.cjs'],
+  moduleNameMapper: {
+    '^@/components/(.*)$': '<rootDir>/components/$1',
+    '^@/pages/(.*)$': '<rootDir>/pages/$1',
+  },
+  testEnvironment: 'jest-environment-jsdom',
+};
+
+module.exports = createJestConfig(customJestConfig);