chore: Counter now embedded with Stimulus

Before this commit, Counter js was autonomous. Now it's registered
like a controller in Stimulus.

app/javascript/application.js

@@ -1,16 +1,3 @@
 // Entry point for the build script in your package.json
 import "@hotwired/turbo-rails"
 import "./controllers"
-import Counter from "./components/counter"
-
-// Initialize counters when DOM is ready
-document.addEventListener('DOMContentLoaded', () => {
-  const counters = document.querySelectorAll('.counter')
-  counters.forEach(counter => new Counter(counter))
-})
-
-// Re-initialize counters on Turbo page loads
-document.addEventListener('turbo:load', () => {
-  const counters = document.querySelectorAll('.counter')
-  counters.forEach(counter => new Counter(counter))
-})