ember-bootstrap with LESS -- application css not transpiling

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