[BUGFIX] Make styles.content.get available after major FSC rewrite

Since the major rewrite of EXT:fluid_styled_content and
EXT:css_styled_content the following TypoScript setup must
be loaded by default:

* `styles.content.get` can be used as ready2use `CONTENT`
  object for `colPos = 0`
* `tt_content.default` outputs necessary info in the frontend,
  if the CType has currently no rendering definition

Both can be used independently from FSC or CSC.

Including the necessary TypoScript via `addTypoScriptSetup()`
takes care of loading it before any other activated extension.

Resolves: #80044
Related: #79622
Releases: master
Change-Id: I460ed9f57e215be96ee13d6714cd522882fb53eb
Reviewed-on: https://review.typo3.org/51884


Tested-by: TYPO3com <no-reply@typo3.com>
Tested-by: Daniel Goerz <ervaude@gmail.com>
Reviewed-by: Johannes Kasberger <johannes.kasberger@reelworx.at>
Tested-by: Johannes Kasberger <johannes.kasberger@reelworx.at>
Tested-by: Daniela Grammlich <grammlich@punkt.de>
Reviewed-by: Markus Klein <markus.klein@typo3.org>
Tested-by: Markus Klein <markus.klein@typo3.org>