feat(completion): add `copilot-cmp`

[corintho]

📑 Description

Adds a new way to integrate copilot with cmp, besides the current options available. This one puts copilot within cmp, instead of setting it up in parallel with it.

[github-actions[bot]]

Review Checklist

Does this PR follow the [Contribution Guidelines](development guidelines)? Following is a partial checklist:

Proper conventional commit scoping:

• If you are adding a new plugin, the scope would be the name of the category it is being added into. ex. feat(utility): added noice.nvim plugin

• If you are modifying a pre-existing plugin or pack, the scope would be the name of the plugin folder. ex. fix(noice-nvim): fix LSP handler error

• [x] Pull request title has the appropriate conventional commit type and scope where the scope is the name of the pre-existing directory in the project as described above

• [x] README is properly formatted and uses fenced in links with <url> unless they are inside a [title](url)

• [x] Proper usage of opts table rather than setting things up with the config function.

[corintho]

Hi Uzaaft, what do you mean by the naming convention for the folder? I am looking at it and I do not see how it could be any different than the one used, which also sits along with other copilot configurations

[corintho]

Thinking about it further, I think you want me to use copilot-lua-cmp as a plugin folder name. But that name is already taken by another configuration with copilot and cmp. Although that one focus on having copilot outside of cmp, but both of them working together. Mine focus on having copilot show within cmp and a regular completion option

[Uzaaft]

This should be copilot-cmp.

[corintho]

I like it because it is less intrusive, but now I got curious to see how other options perform compared to this one