feat: nixvim config

currently only for dnsc-air. can simply be imported in other hosts

modules/nixvim/default.nix

@@ -0,0 +1,26 @@
+{ ... }:
+
+# These options are imported in nixvim.imports and therefore
+# every option here lives within `programs.nixvim`
+{
+  enable = true;
+  defaultEditor = true;
+
+  # Setup some aliases
+  vimAlias = true;
+  vimdiffAlias = true;
+
+  imports = [
+    ./colorscheme.nix
+    ./completion.nix
+    ./editing.nix
+    ./picker.nix
+    ./formatter.nix
+    ./git.nix
+    ./lsp.nix
+    ./options.nix
+    ./statusline.nix
+    ./keybindings.nix
+    ./ai.nix
+  ];
+}