[TASK] Clean up data submission handling

The patch encapsulates the data submission that can feed
DataSubmissionController from index_ts to
TypoScriptFrontendController.

Change-Id: I3d357f97f77db5e675f4ec446fc3015214e372a2
Resolves: #47158
Related: #47157
Releases: 6.1
Reviewed-on: https://review.typo3.org/19826
Reviewed-by: Anja Leichsenring
Tested-by: Anja Leichsenring
Reviewed-by: Wouter Wolters
Tested-by: Wouter Wolters
Reviewed-by: Thomas Maroschik
Tested-by: Thomas Maroschik
Reviewed-by: Christian Kuhn
Tested-by: Christian Kuhn