Enhance form submissions column management (#691)

* Enhance form submissions column management

* Modernize UI components with Nuxt UI and improved styling

- Refactor RecordOperations component to use UButtonGroup and UButton
- Update FormSubmissions component with Nuxt UI buttons and modal
- Improve table cell styling in OpenTable component
- Simplify column management and export functionality

---------

Co-authored-by: Julien Nahum <julien@nahum.net>

client/components/open/components/RecordOperations.vue

@@ -1,46 +1,20 @@
 <template>
-  <div class="flex items-center justify-center space-x-1">
-    <button
+  <UButtonGroup size="xs" orientation="horizontal">
+    <UButton
       v-track.delete_record_click
-      class="border rounded py-1 px-2 text-gray-500 dark:text-gray-400 hover:text-blue-700"
+      size="sm"
+      color="white"
+      icon="heroicons:pencil-square"
       @click="showEditSubmissionModal = true"
-    >
-      <svg
-        xmlns="http://www.w3.org/2000/svg"
-        fill="none"
-        viewBox="0 0 24 24"
-        stroke-width="1.5"
-        stroke="currentColor"
-        class="w-4 h-4"
-      >
-        <path
-          stroke-linecap="round"
-          stroke-linejoin="round"
-          d="m16.862 4.487 1.687-1.688a1.875 1.875 0 1 1 2.652 2.652L6.832 19.82a4.5 4.5 0 0 1-1.897 1.13l-2.685.8.8-2.685a4.5 4.5 0 0 1 1.13-1.897L16.863 4.487Zm0 0L19.5 7.125"
-        />
-      </svg>
-    </button>
-    <button
+    />
+    <UButton
       v-track.delete_record_click
-      class="border rounded py-1 px-2 text-gray-500 dark:text-gray-400 hover:text-red-700"
+      size="sm"
+      color="white"
+      icon="heroicons:trash"
       @click="onDeleteClick"
-    >
-      <svg
-        xmlns="http://www.w3.org/2000/svg"
-        fill="none"
-        viewBox="0 0 24 24"
-        stroke-width="1.5"
-        stroke="currentColor"
-        class="w-4 h-4"
-      >
-        <path
-          stroke-linecap="round"
-          stroke-linejoin="round"
-          d="M14.74 9l-.346 9m-4.788 0L9.26 9m9.968-3.21c.342.052.682.107 1.022.166m-1.022-.165L18.16 19.673a2.25 2.25 0 01-2.244 2.077H8.084a2.25 2.25 0 01-2.244-2.077L4.772 5.79m14.456 0a48.108 48.108 0 00-3.478-.397m-12 .562c.34-.059.68-.114 1.022-.165m0 0a48.11 48.11 0 013.478-.397m7.5 0v-.916c0-1.18-.91-2.164-2.09-2.201a51.964 51.964 0 00-3.32 0c-1.18.037-2.09 1.022-2.09 2.201v.916m7.5 0a48.667 48.667 0 00-7.5 0"
-        />
-      </svg>
-    </button>
-  </div>
+    />
+  </UButtonGroup>
   <EditSubmissionModal
     :show="showEditSubmissionModal"
     :form="form"