Downgrade fsfe/reuse image version from latest to 2.1.0-debian. Two days ago 3.0 was released, which complains about * .devcontainer/devcontainer.json and
* .vscode/settings.json, which both are licensed.

- adds missing header to files
- unify header
- add SPDX (https://spdx.dev/) identifier to header (first step for getting REUSE https://reuse.software/ compliant)
- reworked doxgen

- uses awesome doxygen theme: https://jothepro.github.io/doxygen-awesome-css/

Adresses: #183

- adds wiki pages to doxygen page
- adds doxygen modules for production code and tests

Write artifacts for multi gpu jobs only on failure. Removes clang build analyzer and include_what_you_use job, as the results are not used currently.

Update ci jobs to new image 1.1. Add clangd file to satisfy clangd when indexing cuda files. For the same reason disable cuda response files for includes.