Search is only specific for `nix search`

[Alessandro Candido]

Despite what stated in

https://zero-to-nix.com/start/nix-search#system-specificity

only nix search show the (e.g.) x86_64-linux results alone, while:

• on search.nixos.org the filter should be manually toggled
• nix flake show show all the platforms, e.g.

❯ nix flake show github:nix-community/nurl
github:nix-community/nurl/6e6b91ea715dcdc2dc433450318d99ba01e76638
├───devShells
│   ├───aarch64-darwin
│   │   └───default omitted (use '--all-systems' to show)
│   ├───aarch64-linux
│   │   └───default omitted (use '--all-systems' to show)
│   ├───x86_64-darwin
│   │   └───default omitted (use '--all-systems' to show)
│   └───x86_64-linux
│       └───default: development environment 'nix-shell'
├───formatter
│   ├───aarch64-darwin omitted (use '--all-systems' to show)
│   ├───aarch64-linux omitted (use '--all-systems' to show)
│   ├───x86_64-darwin omitted (use '--all-systems' to show)
│   └───x86_64-linux: package 'nixpkgs-fmt-1.3.0'
├───overlays
│   └───default: Nixpkgs overlay
└───packages
    ├───aarch64-darwin
    │   └───default omitted (use '--all-systems' to show)
    ├───aarch64-linux
    │   └───default omitted (use '--all-systems' to show)
    ├───x86_64-darwin
    │   └───default omitted (use '--all-systems' to show)
    └───x86_64-linux
        └───default: package 'nurl-0.3.13'