Improve content display overrides

Hey I wanted to take this one but its not clear.

• Disable the UI Patterns Source field in Entity Form Display by default. I think this is only possible in UI Patterns because it is a configuration in the field type.
  • Translation is not clear for me. What do we support?
  • Synchronized or asynchron. Asynchron propably works already because this is a field. Do we support synchronized? (Which is actually the more relevant one from my point of view.)
  • Do we use Inline Blocks /Paragraphs for content so translation is mostly done in entities or do we use Components? Or both?
• Do we need to add messages like Layout builder does: " You are editing the layout template for all Basic page content items. " "You are editing the layout for this Basic page content item. Edit the template for all Basic page content items instead."
  >> This is clear
• Unlimited vs limited cardinality: do we warn the user some sources positioned at the root may be removed at save? do we prevent the addition?
  >> The simplest soultion would be a "Help text" and filter out non mulit value cardinality
• Displays overrides tabs are automatically generated by EntityOverrideViewLocalTask. Do we make those configurable and managed as a field widgets instead?
  >> We could add a checkbox to hide the tab and than we use field widget to make the field editable inside the edit form. Would be enough for me.

Thansk for your feedbacks. Let's split them in 3 subjects.

Form experience

Disable the UI Patterns Source field in Entity Form Display by default. I think this is only possible in UI Patterns because it is a configuration in the field type.

Displays overrides tabs are automatically generated by EntityOverrideViewLocalTask. Do we make those configurable and managed as a field widgets instead?

>> We could add a checkbox to hide the tab and than we use field widget to make the field editable inside the edit form. Would be enough for me.

Those 2 points are related. It would be great to to find a single solution addressing for both.

Do we need to add messages like Layout builder does: " You are editing the layout template for all Basic page content items. " "You are editing the layout for this Basic page content item. Edit the template for all Basic page content items instead."

>> This is clear

Cool.

Translation

Test translations. See "️Translatability" in 📌 [PoC] Introduce a `ContentTypeTemplate` config entity Active

• Translation is not clear for me. What do we support?
• Synchronized or asynchron. Asynchron propably works already because this is a field. Do we support synchronized? (Which is actually the more relevant one from my point of view.)

So, let's explore the asynchron way. There are already some cool ideas. Let's discuss before starting the work. We can move the task to is dedicated alpha5 issue if needed.

Do we use Inline Blocks /Paragraphs for content so translation is mostly done in entities or do we use Components? Or both?

This will be addressed by adding/tweaking some sources with the content context. So, out of the scope of this issue.

Storage model

Unlimited vs limited cardinality: do we warn the user some sources positioned at the root may be removed at save? do we prevent the addition?

>> The simplest solution would be a "Help text" and filter out non mulit value cardinality

We need to go further than a help text. Moved to its own beta issue 📌 Cardinality constraint for slots Active