599cf1ce

By: Lucien Huber <im@lcnbr.ch>

include compile-time fixtures in nix test sources

Keep the package-specific Nix test closures aligned with Rust include_str! inputs so both the GammaLoop renormalization tests and the FeynKit momentum-dot integration test compile in isolated Nix builds.

User request:

Continue but I paused the goal as I want you to do a final polishing round, identifying the main important issues left and finishing what you were doing and then do one last clean commit+push and pause/stop there.