Upgrade to horizon-flake-parts 0.16.0
Summary
- Migrate from flake-parts + import-tree to nixica 0.1.0
- Update horizon-flake-parts from 0.10.0 to 0.16.0
- Convert all modules to
local:pattern - Follow nixpkgs from horizon-flake-parts
- Update .gitlab-ci.yml remote template from 0.8.0 to 0.19.0