Windows CI cannot report static-initialisation faults

`nix copy --to` caches the narinfo it uploaded, so the pusher rejects its own paths from caches that sign on serve

Allow `tryEval` to catch `import` parse errors

During upgrade: Assertion 'result == ecSuccess || result == ecFailed || result == ecNoSubstituters' failed

Install Error

“Oh no, something went wrong” while installing

`nix-env` warns that `--option use-xdg-base-directories` is ignored but it is in fact applied

Make `nix search` be able to use search.nixos.org 's cache

Better document commit bit access and what it entails

`nix search` writes excessive diagnostics to stderr