Refactor js registration and generator implementation

[SethHorsley]

Update the RBUI js integration in Rails

This PR changes the js integration of RBUI (Ruby UI) into a Rails application

Details

1. Update app/javascript/application.js

Added the following import to integrate RBUI components:

import "../components/rbui";

2. Create or update app/components/rbui/index.js

Added the following import to integrate RBUI components:

import { application } from "../../../app/javascript/controllers/application";

// Import all controller files
// import ComboboxController from "./combobox/combobox_controller";

// Register all controllers
// application.register("rbui--combobox", ComboboxController);

import RBUI from "rbui-js";
RBUI.initialize(application);

@marcoroth helped with this implementation

[SethHorsley]

this is a double check review