broot: Add nushell integration

[takac]

Description

Add additional config flag enableNushellIntegration in broot.nix to setup broot/br for nushell.

Checklist

• Change is backwards compatible.

• Code formatted with ./format.

• Code tested through nix-shell --pure tests -A run.all or nix develop --ignore-environment .#all using Flakes.

• Test cases updated/added. See example.

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Maintainer CC

@aheaume @dermetfan

[dermetfan]

With Nushell 0.87.0 and broot 1.27.0 (which are currently in 23.11) I get this error message on startup:

Error:   × Deprecated command
    ╭─[/nix/store/gdwnbsz8wxrgg6iy2prraj3d6yill27p-br.nushell:10:1]
 10 │ # See https://dystroy.org/broot/install-br/
 11 │ def-env br [
    · ───┬───
    ·    ╰── `def-env` is deprecated and will be removed in 0.88.
 12 │     --cmd(-c): string               # Semicolon separated commands to execute
    ╰────
  help: Use `def --env` instead

The script still works so this is not a hard error but certainly ugly.

However, I believe it is still the right decision to merge for the following reasons:

1. This is an issue with broot. They will likely fix this and we won't have to change any code, so the problem will disappear by itself.
2. programs.zoxide.enableNushellIntegration has the same issue and is also enabled by default.
3. While the default is to enable nushell integration, users are still free to disable it.

I will merge in the coming days if no one raises concerns.

[dermetfan]

Thanks for your contribution!