pkgs: add meta attr

Also add more detailed `enable` option descriptions.

pkgs/spark-wallet/default.nix

@@ -1,8 +1,16 @@
-{ pkgs }:
+{ pkgs, lib }:
 let
   nodePackages = import ./composition.nix { inherit pkgs; };
 in
 nodePackages.package.override {
   # Required because spark-wallet uses `npm-shrinkwrap.json` as the lock file
   reconstructLock = true;
+
+  meta = with lib; {
+    description = "A minimalistic wallet GUI for c-lightning";
+    homepage = "https://github.com/shesek/spark-wallet";
+    license = licenses.mit;
+    maintainers = with maintainers; [ nixbitcoin earvstedt ];
+    platforms = platforms.unix;
+  };
 }