Rethink Cachy Browser

Cachy Browser currently makes following changes:
- Apply some librewolf patches
- Apply Gentoo patches
- Add a more privacy friendly config

Generally, most of these are already covered by the librewolf browser and therefore this is not really special.

We think about on working on following:
- Find a better mix between privacy and speed of the browser, as well as usability (Dont delete cookies on close, and such things)
- Optimize the browser with the config
- Make it more user friendly

No files, tests, or entry points are named. Start by reviewing the existing LibreWolf and Gentoo patches and the privacy-focused configuration described in the issue; the work is done only after a concrete, agreed scope for privacy, speed, optimization, and usability is defined.

Written by the indexing model from the issue text.