feat(main): Add base theme: This is the falcon theme out of the box.

This is falcon v3.1.2

_dev/js/theme/utils/DynamicImportHandler.js

@@ -0,0 +1,51 @@
+import DynamicImportJqueryPlugin from '@js/theme/utils/DynamicImportJqueryPlugin';
+import DynamicImportDOMEvents from '@js/theme/utils/DynamicImportDOMEvents';
+
+export default class DynamicImportHandler {
+  constructor({
+    files,
+    jqueryPluginCover = null,
+    enableObserve = false,
+    observeOptions = false,
+    DOMEvents = false,
+    DOMEventsSelector = false,
+    DOMEventsPreventDefault = false,
+    onLoadFiles = () => {},
+  } = {}) {
+    this.files = files;
+    this.jqueryPluginCover = jqueryPluginCover;
+    this.enableObserve = enableObserve;
+    this.observeOptions = observeOptions;
+    this.onLoadFiles = onLoadFiles;
+
+    this.jqueryDynamicImport = false;
+    this.dynamicDOMEvents = false;
+    this.filesLoaded = false;
+
+    if (jqueryPluginCover) {
+      this.jqueryDynamicImport = new DynamicImportJqueryPlugin({
+        jqueryPluginCover,
+        importer: this,
+      });
+    }
+    if (DOMEvents && DOMEventsSelector) {
+      this.dynamicDOMEvents = new DynamicImportDOMEvents({
+        events: DOMEvents,
+        eventSelector: DOMEventsSelector,
+        preventDefault: DOMEventsPreventDefault,
+        importer: this,
+      });
+    }
+  }
+
+  loadFiles(callback = () => {}) {
+    if (!this.filesLoaded) {
+      Promise.all(this.files()).then((res) => {
+        callback();
+        this.onLoadFiles(res);
+      });
+
+      this.filesLoaded = true;
+    }
+  }
+}