If not intending to use it for Simulation, then a footprint of pads and a 3D model for Graphic only is included in Kicad (for a basic DIP Chip)… attached image shows example.
You can select the appropriated Pin/Row spacing and pad preference… (I just grabbed the W15.24mm row pitch item…)
You could start a Github or Gitlab repo and put your works there. If you annotate it sufficiently it should be discoverable by search. But I don’t bother with mine as they are often one-offs or I want to customise them so it’s faster to make my own symbols. For example, in your shoes I would edit the pin labels to only show the function I am actually using in my design to reduce clutter and confusion.
The libraries on gitlab are in V6 (5.99) format, and have to be edited with kicad v5.99.
The libraries on github are in V5 format, but are frozen in preparation of the v6.0 release.
If you want to contribute to the official libraries, you need to run the Nightly Development Builds, witch are not recommended for production use. They can be downloaded here, at the very bottom of the page: