Zero Hydra Failures towards 26.05 NixOS release

NixOS-26.05 is around the corner! The schedule says it should happen around 25 May. Today the release process entered ZHF phase. There most packages with build failures are expected to be addresses by the release date. https://github.com/NixOS/nixpkgs/issues/516381 contains detailed step-by-step to identify interesting packages. This time nixpkgs is full of build failures related to gcc-15 changes…