add back user profiles on subscription form

subscription/static/bundled/subscription/creation-form-existing-user-index.ts

@@ -0,0 +1,25 @@
+document.addEventListener("alpine:init", () => {
+  Alpine.data("existing_user_subscription_form", () => ({
+    loading: false,
+    profileFragment: "" as string,
+
+    async init() {
+      const userSelect = document.getElementById("id_member") as HTMLSelectElement;
+      userSelect.addEventListener("change", async () => {
+        await this.loadProfile(Number.parseInt(userSelect.value));
+      });
+      await this.loadProfile(Number.parseInt(userSelect.value));
+    },
+
+    async loadProfile(userId: number) {
+      if (!Number.isInteger(userId)) {
+        this.profileFragment = "";
+        return;
+      }
+      this.loading = true;
+      const response = await fetch(`/user/${userId}/mini/`);
+      this.profileFragment = await response.text();
+      this.loading = false;
+    },
+  }));
+});