add snacks as an optional replacement for telescope

[szechp]

This MR adds a snacks.lua config file that users can optionally enable as a replacement for telescope.

The goal is to allow users to easily swap in snacks.nvim without needing to changing the default configuration too much. This reflects the modular spirit of this fork and avoids the stalled debates around plugin inclusion that have occurred upstream.

This is directly inspired by kickstart.nvim#1481 (I actually just copied @oriori1703's code), which proposes switching from Telescope to Snacks in the main Kickstart repo but has run into decision paralysis due to differing opinions.

Rather than waiting for consensus, this fork can offer both options — cleanly separated — and let users choose what works best for them.

Small changes were made to the default config, because some docstrings and lsp-config contains code that references telescope. i hope i found a good solution for that.

[dam9000]

I think the way the keymaps are handled here could be improved, by moving the telescope lsp specific keymaps to the telescope plugin and same for snack lsp specific keymaps. In that way one could truly just disable one plugin and enable the other for an instant switch, instead of having to go through the code and uncomment many of the specified keymaps. Would you agree?

Also I would prefer that this kind of change goes through the upstream kickstart, perhaps there would be a bigger chance of accepting it when presented as an optional plugin than outright replacement for telescope. Could you try that route?

(ps, thanks for the PR and sorry for the late reply)

[szechp]

ok i will try the route upstream :)