updates to nvim config, helix initial setup

nix/home/programs/helix/default.nix

@@ -0,0 +1,47 @@
+{ pkgs, ... }:
+{
+  programs.helix = {
+    enable = true;
+    languages = {
+      language-server.rnix-lsp = {
+        command = "${pkgs.rnix-lsp}/bin/rnix-lsp";
+      };
+
+      language = [
+        {
+          name = "nix";
+          auto-format = true;
+          language-servers = [
+            { name = "rnix-lsp"; }
+          ];
+        }
+      ];
+    };
+    settings = {
+      theme = "catppuccin_mocha";
+      editor = {
+        line-number = "relative";
+        lsp.display-messages = true;
+        cursor-shape = {
+          insert = "underline";
+          normal = "block";
+          select = "block";
+        };
+      };
+      keys = {
+        normal = {
+          g = { a = "code_action"; }; # Maps `ga` to show possible code actions
+          "ret" = [ "move_line_down" "goto_first_nonwhitespace" ]; # Maps the enter key to move to start of next line
+          X = "extend_line_above";
+          D = "delete_char_backward";
+          ";" = "command_mode";
+          "S-ret" = [ "move_line_up" "goto_first_nonwhitespace" ];
+        };
+        insert = {
+          j = { j = "normal_mode"; }; # Maps `jk` to exit insert mode
+        };
+      };
+
+    };
+  };
+}