Cleaned up CMake

[amock]

This cleans up the installation part of the CMake scripts. After following the migration guide (I added to this repo), I was able to run MeshNav successfully with these installation types of lvr2:

• global (/usr/local)
• local ROS 2 ws installation (ros_ws/install)
• local package installation (pre-compiled libraries) (see packaging_notes.md)

Since I changed the cmake interface, I increased the minor version. Maybe we can get fully downwards compatible before merging this (to version 25.1.0).

This change is important to support precompiled binaries of lvr2. I already put a working runner into the repo. It works like this:

• We merge this into the main branch
• We create a release 25.2.0
• Then a automatic job is triggered that is building and packaging everything and updates the release

[JustusBraun]

Depending projects compiled without any changes