feat: add many plugins

[redxtech]

Here are a bunch of plugins to add:

• blozneliz/before.nvim
• stevearc/profile.nvim
• NStefan002/screenkey.nvim
• danielfalk/smart-open.nvim
• yoineko/nvim-vtsls
• Bilal2453/luvit-meta
• redxtech/nix-reaver.nvim
• OXY2DEV/markview.nvim

I've got a few more that I'd like to add to a later PR, but those require a build step. I'll wait until we work it out in #113 before making a new PR with those.

The plugins with required build step:

• romgrk/fzy-lua-native
• krivahtoo/silicon.nvim
• willothy/moveline.nvim - already in NixNeovimPlugins, but doesn't work as it lacks the build step.