Fix workspace name-only update rejected by required brand fields

The Workspace and Brand settings tabs both submit to the same
updateSettings endpoint, but the Workspace tab sends only the name.
UpdateWorkspaceRequest marked brand_font and image_style as required,
so the name-only request failed validation silently (the form only
renders the name error). Mark both brand fields as sometimes|required
so a name-only update succeeds while the Brand tab still validates them.

Closes #74

app/Http/Requests/App/Workspace/UpdateWorkspaceRequest.php

@@ -29,8 +29,8 @@ public function rules(): array
             'brand_color' => $hex,
             'background_color' => $hex,
             'text_color' => $hex,
-            'brand_font' => ['required', 'string', Rule::in(BrandFont::values())],
-            'image_style' => ['required', 'string', Rule::in(ImageStyle::values())],
+            'brand_font' => ['sometimes', 'required', 'string', Rule::in(BrandFont::values())],
+            'image_style' => ['sometimes', 'required', 'string', Rule::in(ImageStyle::values())],
             'content_language' => ['sometimes', 'string', 'in:en,pt-BR,es'],
         ];
     }

tests/Feature/WorkspaceControllerTest.php

@@ -232,6 +232,27 @@
     expect($this->workspace->refresh()->image_style->value)->toBe('minimalist');
 });
 
+test('update workspace settings updates the name when only the name is submitted', function () {
+    $this->actingAs($this->user)
+        ->from(route('app.workspace.settings'))
+        ->put(route('app.workspace.settings.update'), [
+            'name' => 'Name Only Update',
+        ])
+        ->assertRedirect(route('app.workspace.settings'))
+        ->assertSessionHasNoErrors();
+
+    expect($this->workspace->refresh()->name)->toBe('Name Only Update');
+});
+
+test('update workspace settings still requires brand_font and image_style when submitted empty', function () {
+    $this->actingAs($this->user)
+        ->put(route('app.workspace.settings.update'), [
+            'name' => $this->workspace->name,
+            'brand_font' => '',
+            'image_style' => '',
+        ])->assertSessionHasErrors(['brand_font', 'image_style']);
+});
+
 test('update workspace settings rejects unknown image_style values', function () {
     $this->actingAs($this->user)
         ->put(route('app.workspace.settings.update'), [