[TASK] Add native types to RelationHandler where possible

This change adds native PHP types to RelationHandler.

The reasoning for the changes:
- Even though some properties are public and not typed,
  setting an array property to null will fatal if Relation
  Handler already expects an array access
- Some methods do not get full types, as some options
  can be string/int etc, whereas $tableName must be a
  string in any case, where a type is applied.

This is a pre-patch as part of a bigger change in order
to bring TcaSchema API and Record API into RelationHandler.

Resolves: #104334
Releases: main
Change-Id: I66c6ae10858d6a2bb37ee03792e191b755bd1968
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/85105


Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: Georg Ringer <georg.ringer@gmail.com>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>
Reviewed-by: Georg Ringer <georg.ringer@gmail.com>
Tested-by: core-ci <typo3@b13.com>