Add commands to copy link and open in browser

[luisdavim]

Something similar to https://github.com/f-person/git-blame.nvim?tab=readme-ov-file#commands but having it here would avoid needed extra plugins just for that.

Some examples:

• https://github.com/f-person/git-blame.nvim
• https://github.com/ruifm/gitlinker.nvim
  (https://github.com/linrongbin16/gitlinker.nvim)
• https://github.com/folke/snacks.nvim/blob/main/docs/gitbrowse.md

Thanks