add calendar programs

groups/yezelhlev/programs.nix

@@ -21,6 +21,7 @@
     croc # e2ee file transfer
     chawan # tui browser cha <url>
     shellcheck # sh warning
+    calcure # calendar app TODO: remove & fork calendar.vim
 
     # editors
     lunarvim

homes/modules/vim/nixcats.nix

@@ -85,6 +85,7 @@ in
               nvim-web-devicons
               base16-nvim
               mini-nvim
+              calendar-vim
 
               (pkgs.vimUtils.buildVimPlugin {
                 pname = "candyland-nvim";