feat: add Stimulus dropdown controller

assets/controllers/dropdown_controller.js

@@ -0,0 +1,24 @@
+import { Controller } from '@hotwired/stimulus';
+
+export default class extends Controller {
+    static targets = ['menu', 'trigger'];
+
+    connect() {
+        this._closeOnClickOutside = this._closeOnClickOutside.bind(this);
+        document.addEventListener('click', this._closeOnClickOutside);
+    }
+
+    disconnect() {
+        document.removeEventListener('click', this._closeOnClickOutside);
+    }
+
+    toggle() {
+        this.menuTarget.hidden = !this.menuTarget.hidden;
+    }
+
+    _closeOnClickOutside(event) {
+        if (!this.element.contains(event.target)) {
+            this.menuTarget.hidden = true;
+        }
+    }
+}