notes: fix script, use pkgs instead of PATH

pkgs/notes.nix

@@ -1,19 +1,19 @@
 self: with self; ''
   #
-  # ack recursively through notes
+  # rg recursively through notes
   #
-  # uses ack: https://beyondgrep.com
+  # uses ripgrep: https://github.com/BurntSushi/ripgrep
 
   NOTESDIR=~/pub.solar-nc/Notes
-  ACK_PREFIX="ack --files-with-matches"
+  ACK_PREFIX="${rg}/bin/rg --files-with-matches"
   cd $NOTESDIR || exit
   file="$(
       FZF_DEFAULT_COMMAND="$ACK_PREFIX '$1'" \
-      fzf --sort --preview="[[ ! -z {} ]] && ack --colour --context 5 {q} {}" \
+      ${fzf}/bin/fzf --sort --preview="[[ ! -z {} ]] && ack --colour --context 5 {q} {}" \
           --phony -q "$1" \
           --bind "change:reload:$ACK_PREFIX {q}" \
           --preview-window="70%:wrap"
   )" &&
   echo "opening $file" &&
-  bat --theme=TwoDark "$file"
+  ${bat}/bin/bat --theme=TwoDark "$file"
 ''