Order blocks in sidebar doesn't respect layout restrictions: required and fixed position

[avoinea]

order-sidebar-issues.webm

Steps to reproduce the behavior:

1. Go to ControlPanel > Content Types
2. Add new content type: Book
3. Go to Layout for Book and enable editable blocks
4. Click on Title block and then on Settings in the Sidebar
5. Select "Required"
6. Select "Fixed position"
7. Click on the Order tab in Sidebar:
   • You are able to move the Title block and remove it from here.

Expected behavior

1. If a block is required the delete button should not be present in the Sidebar Order Tab
2. If a block has fixed position the drag & drop button should not be present in the Sidebar Order Tab

Software:

• OS: All
• Browser All
• Volto Version 18.x.x
• Plone Version 6.x
• Plone REST API Version 9.x

Additional context