feat: markdown to html script

- add binary: md2html
- nvf: add snack nvim

home/scripts/md2html.nix

@@ -0,0 +1,23 @@
+{ pkgs, ... }:
+let
+  cssStyle = pkgs.fetchurl {
+    url = "https://raw.githubusercontent.com/xz/new.css/refs/heads/master/new.css";
+    hash = "sha256-Xd3AMZOeThsrupQusSLjqv3hbNmcpeTms0ieI9nyxOk=";
+  };
+in
+pkgs.writeShellScriptBin "md2html" ''
+  set -e
+
+  INPUT="$1"
+  shift
+
+  BASENAME="''\${INPUT%.*}"
+  HTML_TEMP="''\${BASENAME}.html"
+  PDF_OUTPUT="''\${BASENAME}.pdf"
+
+  ${pkgs.pandoc}/bin/pandoc "$INPUT" -s \
+  --to=html5 --embed-resources \
+  --css=${cssStyle} -o "$HTML_TEMP" "$@"
+
+  echo "generated: $HTML_TEMP"
+''