feat: snacks.nvim picker integration

[ph1losof]

This PR implements a snacks.nvim picker integration for code actions.

It works in the following way:

1. checks if the user has telescope, if yes then uses it to pick files
2. checks if the user has snacks.nvim, if yes then uses snacks.nvim picker to pick files
3. if none works then displays following notification: Telescope or snacks.nvim picker needs to be installed to call this integration and does a fallback to the manual entry

Further improvement can be done in typescript-tools.nvim config to explicitly state which picker should be used for such operations or none at all.