ember-bootstrap with LESS -- application css not transpiling - ember.js

Question

I'm working on upgrading little-by-little an EmberJS Application that uses ember-bootstrap. Before moving to Ember 4 we are trying to move up to the Ember 3 LTS 3.28.6. However, we have ember-bootstrap using LESS in our project and things have fallen apart a bit because of some dependency mapping that pushes us to newer versions. To avoid migrating to SASS, I'm currently trying to use https://github.com/seanCodes/bootstrap-less-port to keep less for one last iteration. But a curious thing is happening in my local build: the application css is not being generated (.css) is nowhere to be found in dist/assets/ !
The build seems to go just fine (save the long list of deprecation errors).
Anyone have an idea why my appli.css is not generating ?
How would I specify to ember-bootstrap to look for appli.less ? Is this possible ? If it is, it seems the code is here: https://github.com/ember-bootstrap/ember-bootstrap/blob/d98e054abd8ea172bbd47a81655ef300aeae7f87/blueprints/ember-bootstrap/index.js#L103
Maybe I'm being blocked here? https://github.com/ember-bootstrap/ember-bootstrap/blob/d98e054abd8ea172bbd47a81655ef300aeae7f87/blueprints/ember-bootstrap/index.js#L57
package.json
{
"name": "appli",
"version": "1.0.0",
"private": true,
"description": "Small description for appli goes here",
"repository": "",
"license": "MIT",
"author": "",
"directories": {
"doc": "doc",
"test": "tests"
},
"scripts": {
"build": "ember build",
"lint:hbs": "ember-template-lint .",
"lint:js": "eslint .",
"start": "ember serve",
"test": "ember test"
},
"devDependencies": {
"#ember/jquery": "^1.1.0",
"#ember/optional-features": "^2.0.0",
"#ember/test-helpers": "^2.6.0",
"#glimmer/component": "^1.0.4",
"#glimmer/tracking": "^1.0.4",
"babel-eslint": "^10.1.0",
"bootstrap": "^4.6.0",
"bootstrap-less-port": "^2.5.1",
"bootstrap-datepicker": "1.4.0",
"bootstrap-select": "1.7.4",
"broccoli-asset-rev": "^3.0.0",
"browserslist": "^4.21.0",
"codemirror": "^5.50.2",
"ember-ajax": "^5.0.0",
"ember-auto-import": "^1.12.0",
"ember-bootstrap": "^4.9.0",
"ember-cli": "^3.28.6",
"ember-cli-app-version": "^5.0.0",
"ember-cli-babel": "^7.26.10",
"ember-cli-dependency-checker": "^3.2.0",
"ember-cli-file-saver": "^1.2.4",
"ember-cli-htmlbars": "^5.7.2",
"ember-cli-inject-live-reload": "^2.1.0",
"ember-cli-sri": "^2.1.1",
"ember-cli-terser": "^4.0.2",
"ember-copy": "^2.0.1",
"ember-data": "^3.28.6",
"ember-export-application-global": "^2.0.1",
"ember-fetch": "^8.1.1",
"ember-load-initializers": "^2.1.2",
"ember-maybe-import-regenerator": "^0.1.6",
"ember-moment": "^9.0.1",
"ember-page-title": "^6.2.2",
"ember-qunit": "^5.1.5",
"ember-resolver": "^8.0.3",
"ember-source": "~3.28.8",
"ember-template-lint": "^3.15.0",
"ember-welcome-page": "^4.1.0",
"eslint": "^7.32.0",
"eslint-config-prettier": "^8.3.0",
"eslint-plugin-ember": "^10.5.8",
"eslint-plugin-node": "^11.1.0",
"eslint-plugin-prettier": "^3.4.1",
"eslint-plugin-qunit": "^6.2.0",
"handlebars": "3.0.3",
"loader.js": "^4.7.0",
"moment-duration-format": "2.2.2",
"npm-run-all": "^4.1.5",
"prettier": "^2.5.1",
"qunit": "^2.17.2",
"qunit-dom": "^1.6.0",
"select2": "4.0.4",
"underscore": "1.9.1",
"vis": "4.21.0"
},
"engines": {
"node": "12.* || 14.* || >= 16"
},
"dependencies": {
"datatables.net-dt": "^1.10.20",
"datatables.net-plugins": "^1.10.20",
"datatables.net-rowgroup-dt": "^1.1.1",
"less": "^3.13.1"
},
"ember": {
"edition": "octane"
}
}
ember-cli-build.js
'use strict';
const EmberApp = require('ember-cli/lib/broccoli/ember-app');
var Funnel = require('broccoli-funnel');
module.exports = function(defaults) {
let app = new EmberApp(defaults, {
'ember-bootstrap': {
bootstrapVersion: 4,
importBootstrapCSS: false,
},
'lessOptions': {
paths: ['node_modules/bootstrap/less'],
}
});
...
return app.toTree([imgJquery]);
app.less
#import "bootstrap-less-port";
#import "theme";
#import "variables";
#import "panels";
#import (less) "style.css";
#import (less) "datatable.css";
#import (less) "charts.css";
#import (less) "select2.css";
#import (less) "timeline.css";
#import (less) "codemirror.css";
#import (less) "vis-helios.css";
Action: Running
npm run build
Expected:
should generate the appli.css and vendor.css files within dist/assets
Observed:
app.less and app.css.map are present
vendor.css is present