chore(luarocks): add rockspec to publish/install with luarocks

[GuillaumeDesforges]

Description

Allow installation of codecompanion.nvim with luarocks (https://luarocks.org/).

• Added a rockspec file to publish on luarocks.

Having this file does not, in itself, allow users to install via luarocks; it must be uploaded to https://luarocks.org/.
Since I needed to install it, I have gone and pushed this version to https://luarocks.org/modules/gdfrj/codecompanion.nvim; I can transfer ownership if you'd like to publish yourself (e.g. in the CI). Otherwise I can happily do it by hand when notified (ping me via GitHub or email).

Checklist

• I've read the contributing guidelines and have adhered to them in this PR

Well, I have not opened a discussion before. If you don't care you may just close the PR I wan't take it personally. :)

• I've run make all to ensure docs are generated, tests pass and StyLua has formatted my code

Not needed here though

• (optional) I've added test coverage for this fix/feature
• (optional) I've updated the README and/or relevant docs pages

... and wishing you a happy New Year!

[olimorris]

Hey @GuillaumeDesforges thanks for this PR. Absolutely awesome idea and one that I think is worthwhile pursuing.

My immediate thought is...how can we automate this? I think it would be cool to add a release workflow like I have with a Ruby gem so that we're always keeping it up to date.

Potentially we should do the same with the rockspec too? A simple lua script to traverse the CodeCompanion directory and create a rockspec file on our behalf.