feat: Add Jest testing infrastructure with comprehensive mocks and test scripts

- Add jest.config.js with Next.js integration, jsdom environment, module path mapping, and coverage collection for src/**/*.{js,jsx,ts,tsx}
- Add jest.setup.js with @testing-library/jest-dom, Next.js router/navigation mocks, IntersectionObserver/ResizeObserver/WebSocket/fetch mocks, localStorage/sessionStorage mocks
- Add package.json test scripts: test, test:watch, test:coverage
- Add testing dependencies: @testing-library/jest

apps/web-dashboard/jest.config.js

@@ -0,0 +1,20 @@
+const nextJest = require('next/jest.js')
+
+const createJestConfig = nextJest({
+  dir: './',
+})
+
+/** @type {import('jest').Config} */
+const customJestConfig = {
+  setupFilesAfterEnv: ['<rootDir>/jest.setup.js'],
+  moduleNameMapper: {
+    '^@/(.*)$': '<rootDir>/src/$1',
+  },
+  testEnvironment: 'jest-environment-jsdom',
+  collectCoverageFrom: [
+    'src/**/*.{js,jsx,ts,tsx}',
+    '!src/**/*.d.ts',
+  ],
+}
+
+module.exports = createJestConfig(customJestConfig)