feat: add project-nvim to plugin imports

lib/default.nix

@@ -2,8 +2,4 @@
   dag = import ./dag.nix {inherit lib;};
   booleans = import ./booleans.nix {inherit lib;};
   types = import ./types {inherit lib;};
-
-  imports = [
-    ./assertions.nix
-  ];
 }

lib/types/plugins.nix

@@ -78,6 +78,7 @@ with lib; let
     "modes-nvim"
     "vim-repeat"
     "smartcolumn"
+    "project-nvim"
   ];
   # You can either use the name of the plugin or a package.
   pluginsType = with types;