Several changes have been made, primarily around checking the existence of methods and classes and
removing unnecessary comments.

- Method checks have been introduced to ensure the `getCachePath()` method exists before calling it.
- Removed invalid phpDocs, e.g., @var $Site Site and @var $Project Project
- Fixed typing to align return types and updated a factory method to check class existence.
- Added variable definition comments in the settings.css.php file for clarity.

Related: #114

Related: #116

Related: #111

Add QUIQQER Tooling

See merge request !15

(cherry picked from commit 7337c621)

Co-authored-by: Michael Danielczok <michael@pcsg.de>

(cherry picked from commit 09046aec)

Co-authored-by: Michael Danielczok <michael@pcsg.de>

Related: brassberg/tickets#244


(cherry picked from commit 28cc1658)

Co-authored-by: Michael Danielczok <michael@pcsg.de>

fix: quiqqer/quiqqer locale and paths adapted to quiqqer/core

See merge request !13

feat!: quiqqer v2

See merge request !11

feat!: quiqqer v2

See merge request !10

BREAKING CHANGE: quiqqer v2 has been renamed to quiqqer/core. a new major version will be created here so that we can still develop for both versions.