buildCrystalPackage: add copyShardDeps flag

[sund3RRR]

Description of changes

Added the ability to copy dependencies declared in shards.nix instead of creating symbolic links to dependencies. By default, the copyShardDeps flag is set to false, so this change should not break other packages in any way.

This change will have an extremely positive effect on the packaging of crystal packages, since the state of crystal dependencies at the time of download is not final and may change for a number of things:

1. shards.yml may contain a postInstall script that wants to write to the shard's directory (which will lead to build error, because all shards are in /nix/store and they are read only)
2. gi-crystal cannot work in nix, because it generates bindings in its folder, so by creating a link to gi-crystal in /nix/store, we actually prohibit gi-crystal from working and it becomes useless. I patched it and changed the logic of it, so it works at the moment, however, each new version of gi-crystal breaks packages which depends on it, since the version of gi-crystal must match the version from shard.lock
3. crystal macros can be executed at the time of program compilation and write something to the shard's directory. (I ran into this problem in blake3.cr )

With this change, the logic of buildCrystalPackage does not change in any way, but an important setting is added, by adding just one flag, you can create an environment closer to the standard environment and simplify packaging.

Things done

• Built on platform(s)
  • x86_64-linux
  • aarch64-linux
  • x86_64-darwin
  • aarch64-darwin
• For non-Linux: Is sandboxing enabled in nix.conf? (See Nix manual)
  • sandbox = relaxed
  • sandbox = true
• Tested, as applicable:
  • NixOS test(s) (look inside nixos/tests)
  • and/or package tests
  • or, for functions and "core" functionality, tests in lib/tests or pkgs/test
  • made sure NixOS tests are linked to the relevant packages
• Tested compilation of all packages that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review rev HEAD". Note: all changes have to be committed, also see nixpkgs-review usage
• Tested basic functionality of all binary files (usually in ./result/bin/)
• 24.05 Release Notes (or backporting 23.05 and 23.11 Release notes)
  • (Package updates) Added a release notes entry if the change is major or breaking
  • (Module updates) Added a release notes entry if the change is significant
  • (Module addition) Added a release notes entry if adding a new NixOS module
• Fits CONTRIBUTING.md.

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[sund3RRR]

@SuperSandro2000

[nixos-discourse]

This pull request has been mentioned on NixOS Discourse. There might be relevant details there:

https://discourse.nixos.org/t/prs-ready-for-review/3032/3535

[peterhoeg]

Thanks a lot for doing this - I haven't been able to afford the time for a proper review that this deserves, but will take a look in the near future. Please also note that we have a Google Summer of Code project idea related to crystal.

[sund3RRR]

Hi, guys. I want to fix all packages related to this change before the new NixOS 24.05 release. Can someone review this PR, please?

[sund3RRR]

@SuperSandro2000 could you review my PR please?

[sund3RRR]

@SuperSandro2000

[donovanglover]

LGTM

[Artturin]

Please add the description to the commit message then 👍

[sund3RRR]

Please add the description to the commit message then 👍

What description should be added to the commit?

[peterhoeg]

Looks good, thanks @sund3RRR

[Artturin]

Please add the description to the commit message then 👍

What description should be added to the commit?

The pull request description, it's good to have it in the commit because github can at any moment remove PRs and has done so many times before.

It's good for writing docs too https://github.com/NixOS/nixpkgs/blob/master/doc/languages-frameworks/crystal.section.md