refactor: migrate to ES Modules and Rollup

- Transitioned src/angular-chart.js to native import/export syntax.
- Introduced Rollup to generate UMD, ESM, and CJS bundles.
- Added live-reload development loop with `npm run dev`.
- Updated package.json with `module` and `exports` for modern tool compatibility.
- Updated examples and test fixtures to point to dist/ bundles.
- Cleaned up legacy JS bundling and minification logic from gulpfile.js.
- Configured ESLint and Karma to support the new module structure.

Author: jtblin

.eslintrc.json

@@ -59,6 +59,15 @@
     "angular/no-service-method": "off"
   },
   "overrides": [
+    {
+      "files": ["src/**/*.js", "rollup.config.js"],
+      "parserOptions": {
+        "sourceType": "module"
+      },
+      "rules": {
+        "strict": "off"
+      }
+    },
     {
       "files": ["test/**/*.js"],
       "globals": {

CONTRIBUTING.md

@@ -3,8 +3,10 @@
 1. Create an issue
 1. Fork the repo
 1. Install dependencies: `npm install`
-1. Make your changes and add tests
 1. This project follows the [Google JavaScript Style Guide](https://google.github.io/styleguide/jsguide.html).
+1. Use `npm run dev` for a live-reload development loop.
+1. Make your changes in `src/` and add tests.
 1. Ensure your code is lint-free: `npm run lint`
-1. Run tests: `npm test`
+1. Run tests: `npm test` (this will run lint, unit, and integration tests).
+1. Ensure the build works: `npm run build`
 1. Submit pull request

README.md

@@ -34,10 +34,20 @@ but must be set via standard options e.g. `ChartJsProvider.setOptions({ responsi
 
     npm install --save angular-chart.js
 
-### cdn
-
     https://cdn.jsdelivr.net/npm/angular-chart.js@latest/dist/angular-chart.min.js
 
+### ESM / Modern Bundlers
+
+If you are using a modern bundler like Vite, Webpack 5, or Rollup:
+
+```javascript
+import angular from 'angular';
+import Chart from 'chart.js';
+import angularChart from 'angular-chart.js';
+
+angular.module('app', [angularChart]);
+```
+
 ### manually
 
 or copy the files from `dist/`. 
@@ -250,7 +260,29 @@ See [CONTRIBUTING.md](CONTRIBUTING.md).
 
 # Development
 
-This project uses [ESLint](https://eslint.org/) to enforce the [Google JavaScript Style Guide](https://google.github.io/styleguide/jsguide.html). 
+This project uses **Rollup** for bundling and **Gulp** for task automation.
+The source code is located in `src/` and uses native ES Modules.
+
+## Local Development Loop
+
+To start the development server with live reload:
+
+```bash
+npm run dev
+```
+
+This will:
+1. Start a local server at `http://localhost:8045`.
+2. Watch `src/` for changes and rebuild the `dist/` files instantly.
+3. Automatically reload the browser when changes are detected.
+
+## Building
+
+To generate the production bundles in `dist/`:
+
+```bash
+npm run build
+```
 
 ## Linting