[TASK] Keep implementation, schema and documentation in sync

[schliesser]

The JSON schemas, the Field Type classes and the YAML reference had drifted apart: valid configuration was rejected by content-blocks:lint, while other properties were allowed but never read at runtime.

Align all three sides:

• Schema: add sortItems (Country), default (Pass, Language), size (DateTime), format and mode (Textarea), localizeReferencesAtParent- Localization (Collection), ignoreIfNotInPalette (Linebreak); drop valuePicker (Country) and default (Slug); correct the required default of Uuid.
• Implementation: honour size (Email), required (Uuid), autoSizeMax (Select) and valuePicker (Textarea); drop appearance (Relation), which TCA type "group" does not evaluate.
• Support itemsProcFunc, itemsProcessors and itemsProcConfig for SelectText and SelectNumber, which core resolves for every TCA type "select" regardless of renderType.

Add two guards so the three sides cannot drift again: SchemaFieldTypeSyncTest covers schema <-> implementation, and Build/Scripts/checkDocumentationSync.php reports schema <-> documentation. Both derive Field Types, their settings, their schema branch and the centrally declared properties from the sources themselves, so adding a Field Type needs no bookkeeping.

Resolves: #562

[nhovratov]

@schliesser thanks! This is massive.. will need to check and verify whether these are all valid.

Regarding SelectText and SelectNumber: These are by intention without item processors, so the DefaultSchema can automatically derive a varchar / int DB field. So this can be removed again.

Give me some time to read this thoroughly.

[schliesser]

@nhovratov thank you very much for reviewing it. Yes it got massive quiet quickly 🙈

The SelectText and SelectNumber fields have no item processors anymore. SelectText did make use of Trait WithCustomProperties, which is removed now.

Let me know what else to change :-)

[nhovratov]

@schliesser Perfect. I only removed required from type Language, which was wrong all along. I think we can keep your tests. They are quite useful to have for contribution.