[INFRA] Simplify demo CSS watch configuration

docs/contributors/demo-page-css.md

@@ -4,10 +4,8 @@ The project demo page uses [tailwindcss](https://tailwindcss.com/docs).
 To process the CSS rules and get an output `tailwind.css` file, which is used in demo page:
 run: `npm run demo`
 
-Sub job `demo:css` does the trick, it uses postcss. Feel free to preview config files:
+The `demo:css` npm script does the trick, it uses postcss. Feel free to preview config files:
 - [postcss.config.js](postcss.config.js)
 - [tailwind.config.js](tailwind.config.js)
 
-The Rollup build is updated to handle livereload, there are 2 scripts in [package.json](../../package.json) that permits that: \
-1. Build the output tailwind.css file: `demo:css`
-2. Watch for the changes in html and styles.css. `watch:css`
+The Rollup build handles the livereload and the html/css resources watch.

package.json

@@ -61,7 +61,6 @@
     "docs:api": "typedoc --tsconfig ./tsconfig.typedoc.json src/bpmn-visualization.ts",
     "start": "rollup -c --silent --environment devMode:true",
     "watch": "rollup -cw --environment devLiveReloadMode:true",
-    "watch:css": "chokidar \"dev/public/static/css/styles.css\" \"dev/public/*.html\" --command \"npm run demo:css\" --verbose",
     "lint": "eslint \"*/**/*.{js,ts}\" NOTICE --max-warnings 0 --quiet --fix",
     "lint-check": "eslint \"*/**/*.{js,ts}\" NOTICE --max-warnings 0",
     "test": "run-s test:unit test:integration test:e2e",
@@ -106,7 +105,6 @@
     "@typescript-eslint/parser": "^5.9.1",
     "asciidoctor": "^2.2.5",
     "autoprefixer": "^10.4.2",
-    "chokidar-cli": "^3.0.0",
     "clipboardy": "^3.0.0",
     "cross-env": "^7.0.3",
     "cssnano": "^5.0.15",

rollup.config.js

@@ -150,7 +150,7 @@ function pluginsForDevelopment() {
   if (devMode || demoMode) {
     plugins.push(execute('npm run demo:css', true)); // sync to ensure the execution is linked to the main rollup process
     if (devLiveReloadMode) {
-      plugins.push(execute('npm run watch:css'));
+      plugins.push(execute('npm run demo:css -- --watch --verbose'));
     }
 
     const copyTargets = [];