feat: registration field polish, multi-category tags, file uploads, Partner icon

- Restructure field editor dialog: move Options section to bottom with
  divider and subheader, fix delete button with flex layout
- Change tag_category (single string) to tag_categories (JSON array)
  supporting multiple category selection in tag picker fields
- Portal tag picker now groups tags by category with subheaders
- Add generic file upload endpoint (FileUploadService + UploadController)
- Replace email branding logo URL text field with ImageUploadField
- Update Partner crowd type default icon to tabler-affiliate
- Apply changes consistently to both field and template dialogs

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

api/app/Http/Controllers/Api/V1/PublicRegistrationDataController.php

@@ -98,7 +98,7 @@ final class PublicRegistrationDataController extends Controller
                         'field_type' => $field->field_type->value,
                         'options' => $field->options,
                         'normalized_options' => $field->normalized_options,
-                        'tag_category' => $field->tag_category,
+                        'tag_categories' => $field->tag_categories,
                         'is_required' => $field->is_required,
                         'help_text' => $field->help_text,
                         'display_width' => $field->display_width->value,
@@ -108,11 +108,11 @@ final class PublicRegistrationDataController extends Controller
                         $query = PersonTag::where('organisation_id', $organisationId)
                             ->where('is_active', true);
 
-                        if ($field->tag_category) {
-                            $query->where('category', $field->tag_category);
+                        if (!empty($field->tag_categories)) {
+                            $query->whereIn('category', $field->tag_categories);
                         }
 
-                        $data['available_tags'] = $query->orderBy('sort_order')
+                        $data['available_tags'] = $query->orderBy('category')->orderBy('sort_order')
                             ->get()
                             ->map(fn (PersonTag $tag) => [
                                 'id' => $tag->id,

api/app/Http/Controllers/Api/V1/UploadController.php

@@ -0,0 +1,52 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Http\Controllers\Api\V1;
+
+use App\Http\Controllers\Controller;
+use App\Services\FileUploadService;
+use Illuminate\Http\JsonResponse;
+use Illuminate\Http\Request;
+
+final class UploadController extends Controller
+{
+    public function __construct(
+        private readonly FileUploadService $uploadService,
+    ) {}
+
+    public function uploadImage(Request $request): JsonResponse
+    {
+        $request->validate([
+            'file' => ['required', 'file', 'max:5120'],
+            'purpose' => ['required', 'string', 'in:logo,banner,icon,avatar'],
+        ]);
+
+        $user = $request->user();
+        $organisation = $user->organisations()->first();
+
+        try {
+            $url = $this->uploadService->uploadImage(
+                file: $request->file('file'),
+                directory: 'uploads/' . $request->input('purpose'),
+                organisationId: $organisation?->id,
+            );
+        } catch (\DomainException $e) {
+            return response()->json(['message' => $e->getMessage()], 422);
+        }
+
+        activity('upload')
+            ->causedBy($user)
+            ->withProperties([
+                'purpose' => $request->input('purpose'),
+                'original_name' => $request->file('file')->getClientOriginalName(),
+                'size_bytes' => $request->file('file')->getSize(),
+                'mime' => $request->file('file')->getMimeType(),
+            ])
+            ->log('image.uploaded');
+
+        return response()->json([
+            'data' => ['url' => $url],
+        ]);
+    }
+}