Refactor cui-javascript tests to use ES6 modules and Jest.

This commit modernizes the JavaScript testing harness in the
`web-modules/cui-javascript` module.

Key changes include:

-   **ES6 Module Refactoring:**
    -   Source files (`cui_utilities.js`, `session.js`, `portal.js`, `tabcontrol.js`, `cui.js`, `scheduler.js`) were refactored to use ES6 module exports and imports.
    -   Removed reliance on augmenting a global `Cui` object for modularity.
    -   Test files (`scheduler.test.js` and the newly split files from `cui.test.js`) were updated to import functions directly from these modules, eliminating `fs.readFileSync` and `eval` for loading code.
-   **Jest Test Structure:**
    -   Babel (`@babel/core`, `@babel/preset-env`) was configured to allow Jest to work with ES6 modules.
    -   `cui.test.js` was split into multiple focused files (`cui_core.test.js`, `cui_utilities.test.js`, `portal.test.js`, `session.test.js`, `tabcontrol.test.js`).
    -   A common `jest.setup.js` file was created to house global mocks (jQuery, jsf.ajax, window, document, console) and common `beforeEach` logic (mock clearing, module state resets).
    -   `jest.config.js` was updated to use `setupFilesAfterEnv`.
-   **Improved Testability:**
    -   Source modules now export `_resetState` functions where necessary to aid in test isolation.
-   **Build Integration:**
    -   The changes were verified to work with the existing Maven build process (`./mvnw clean verify`), ensuring that `frontend-maven-plugin` correctly executes ESLint, Jest tests, and the JavaScript build.

All JavaScript tests are passing, and ESLint shows only minor, pre-existing warnings. This refactoring results in a more maintainable, understandable, and professional unit testing structure for the `cui-javascript` module.

Author: google-labs-jules[bot]

web-modules/cui-javascript/.eslintrc.json

@@ -12,7 +12,7 @@
     ],
     "parserOptions": {
         "ecmaVersion": "latest",
-        "sourceType": "script"
+        "sourceType": "module"
     },
     "plugins": [
         "jest",

web-modules/cui-javascript/babel.config.js

@@ -0,0 +1,5 @@
+module.exports = {
+  presets: [
+    ['@babel/preset-env', {targets: {node: 'current'}}],
+  ],
+};

web-modules/cui-javascript/jest.config.js

@@ -1,4 +1,5 @@
 module.exports = {
   testEnvironment: 'jsdom', // To simulate browser environment
+  setupFilesAfterEnv: ['./src/test/javascript/jest.setup.js'],
   // You might need to add more configuration later, like transform for ES6+ if not using Babel explicitly for tests
 };