treewide: with stdenv.lib; in meta -> with lib;

Part of: https://github.com/NixOS/nixpkgs/issues/108938

meta = with stdenv.lib;

is a widely used pattern. We want to slowly remove
the `stdenv.lib` indirection and encourage people
to use `lib` directly. Thus let’s start with the meta
field.

This used a rewriting script to mostly automatically
replace all occurances of this pattern, and add the
`lib` argument to the package header if it doesn’t
exist yet.

The script in its current form is available at
https://cs.tvl.fyi/depot@2f807d7f141068d2d60676a89213eaa5353ca6e0/-/blob/users/Profpatsch/nixpkgs-rewriter/default.nix

pkgs/applications/audio/lv2-cpp-tools/default.nix

@@ -1,4 +1,4 @@
-{ stdenv, fetchzip, pkgconfig, lv2, gtkmm2, boost }:
+{ lib, stdenv, fetchzip, pkgconfig, lv2, gtkmm2, boost }:
 
 stdenv.mkDerivation rec {
   pname = "lv2-cpp-tools";
@@ -18,7 +18,7 @@ stdenv.mkDerivation rec {
 
   buildInputs = [ lv2 gtkmm2 boost ];
 
-  meta = with stdenv.lib; {
+  meta = with lib; {
     homepage = "http://ll-plugins.nongnu.org/hacking.html";
     description = "Tools and libraries that may come in handy when writing LV2 plugins in C++";
     license = licenses.gpl3;