[BUGFIX] Show source file and user agent in CSP backend module

The CSP backend module is not showing the optional source-file
of the reported violation. This information references to the
actual asset that caused the violation. In addition, visualizing
the user-agent helps to identifiy and reproduce possible flaws.

In case, `effective-directive` (preferred W3C property) is not
given, but `violated-directive` (legacy W3C property) is, that
value is taken - this still can happen in old browser versions.

Resolves: #100912
Releases: main, 12.4
Change-Id: Idf9482d234292a15a4114c474ddb2b5316d21a87
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/79562


Tested-by: core-ci <typo3@b13.com>
Tested-by: Oliver Hader <oliver.hader@typo3.org>
Reviewed-by: Oliver Hader <oliver.hader@typo3.org>