✨ (bootsier): Añade AdminLTE 4 y Bootstrap Icons

Integra AdminLTE 4.0.0 (SCSS y JS), Bootstrap Icons 1.13.1 y las fuentes
Source Sans 3 VF; reorganiza los SCSS del tema con la nueva estructura
de *pagetop-build*.

extensions/pagetop-bootsier/assets/bootstrap-5.3.8/scss/tests/jasmine.js

@@ -0,0 +1,16 @@
+/* eslint-disable camelcase */
+
+'use strict'
+
+const path = require('node:path')
+
+module.exports = {
+  spec_dir: 'scss',
+  // Make Jasmine look for `.test.scss` files
+  spec_files: ['**/*.{test,spec}.scss'],
+  // Compile them into JS scripts running `sass-true`
+  requires: [path.join(__dirname, 'sass-true/register')],
+  // Ensure we use `require` so that the require.extensions works
+  // as `import` completely bypasses it
+  jsLoader: 'require'
+}