add latex for org mode previews

modules/emacs.nix

@@ -5,9 +5,33 @@
 }:
 
 {
-  environment.systemPackages = with pkgs; [
-    mu
-  ];
+  environment.systemPackages =
+    let
+      # https://wiki.nixos.org/wiki/TexLive
+      # minimal set of latex packages for orgmode
+      # emacs config:
+      # (setq org-latex-complier "lualatex")
+      # (setq org-preview-latex-default-process 'dvisvgm)
+      orgmode-tex = (
+        pkgs.texlive.combine {
+          inherit (pkgs.texlive)
+            scheme-basic
+            dvisvgm
+            dvipng
+            wrapfig
+            amsmath
+            ulem
+            hyperref
+            capt-of
+            ;
+        }
+      );
+    in
+    with pkgs;
+    [
+      mu
+      orgmode-tex
+    ];
 
   services.emacs = {
     install = true;