Add system view fallback (#18536)

## Context
The goal is to add a "See records" button in all objects that would
redirect to that view (this will be done in a later PR). See screenshot
below.
<img width="665" height="312" alt="Screenshot 2026-03-10 at 15 54 36"
src="https://github.com/user-attachments/assets/6e23a75b-cff0-4d93-bce8-b5481b05c6f6"
/>

## Implementation
- If a view does not exist on an object, there is a **temporary**
fallback where the frontend creates the missing view as a custom view
when going over the object index page
- System objects are now surfaced but we don't want their records to be
editable, they will be readonly (mostly, all fields will be non-editable
except for their custom fields).
- We can't create a new record of a system object, some actions are also
hidden.
- The backend now rejects if you are trying to delete the last view of
an object

packages/twenty-front/src/modules/views/view-picker/components/ViewPickerOptionDropdown.tsx

@@ -30,6 +30,7 @@ import {
 
 type ViewPickerOptionDropdownProps = {
   isIndexView: boolean;
+  isLastView: boolean;
   view: Pick<
     View,
     | 'id'
@@ -45,6 +46,7 @@ type ViewPickerOptionDropdownProps = {
 
 export const ViewPickerOptionDropdown = ({
   isIndexView,
+  isLastView,
   onEdit,
   view,
   handleViewSelect,
@@ -149,12 +151,14 @@ export const ViewPickerOptionDropdown = ({
                           closeDropdown(dropdownId);
                         }}
                       />
-                      <MenuItem
-                        LeftIcon={IconTrash}
-                        text={t`Delete`}
-                        onClick={handleDelete}
-                        accent="danger"
-                      />
+                      {!isLastView && (
+                        <MenuItem
+                          LeftIcon={IconTrash}
+                          text={t`Delete`}
+                          onClick={handleDelete}
+                          accent="danger"
+                        />
+                      )}
                     </>
                   )}
                 </>