* convert search into separate endpoints
* move shared functionalty to components
* NOTE: acceptance of opensearch has waned over the last decade and
the script should be updated
* redo page render following the logic of:
Response ─┬─> TextResponse ─> TextResponseImpl
└─> TemplateResponse ─> TemplateResponseImpl
* split up giant files, one per response path
* caching becomes a trait, implemented where necessary
* TextResponses (Ajax) can now be cached
* make use of previously defined php classes for js objects
* Tabs, Listview, Tooltip, Announcement, Markup, Book, ...
* \Aowow\Template\PageTemplate is the new class to be cached
* do not discard error messages generated after vars have been sent to template
and store in session for display at a later time
* implement tracking consent management
* move logic out of template into their respective endpoints
* modernize DB-Types
- long term: should be split in class that describes the DB-Type and container class that handles multiples
* make unchanging filter props static, allow lookup of criteria indizes through filter
* move username/mail/password checks to util and make them usable as input filter
