feat(editors): add nickel setup

- add nickel & nls packages to environment
- setup nickel integrations with neovim

home/editors/lsp.nix

@@ -5,6 +5,7 @@
     # language servers
     omnisharp-roslyn
     nil
+    nls
     buf-language-server
     terraform-ls
     python3Packages.python-lsp-server
@@ -21,6 +22,7 @@
     sumneko-lua-language-server
 
     # linters & formatters
+    topiary
     shellcheck
     shfmt
     nodePackages.eslint

home/editors/neovim/lsp/lsp.lua

@@ -70,6 +70,7 @@ config.html.setup(default_config)
 config.cssls.setup(default_config)
 config.dockerls.setup(default_config)
 config.nil_ls.setup(default_config)
+config.nickel_ls.setup(default_config)
 config.tsserver.setup(default_config)
 config.graphql.setup(default_config)
 config.pylsp.setup(default_config)
@@ -173,6 +174,9 @@ null_ls.setup({
     null_ls.builtins.diagnostics.buf,
     null_ls.builtins.diagnostics.eslint_d,
     null_ls.builtins.diagnostics.stylelint,
+    null_ls.builtins.formatting.topiary.with {
+      filetypes = { "ncl", "nickel" },
+    },
     null_ls.builtins.formatting.shfmt,
     null_ls.builtins.formatting.eslint,
     -- TODO prettier_d_slim isn't working