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/development/web/valum/default.nix

@@ -1,4 +1,4 @@
-{ stdenv, meson, ninja, pkgconfig, fetchFromGitHub, glib, vala, ctpl
+{ lib, stdenv, meson, ninja, pkgconfig, fetchFromGitHub, glib, vala, ctpl
 , libgee, libsoup, fcgi }:
 
 stdenv.mkDerivation rec {
@@ -15,7 +15,7 @@ stdenv.mkDerivation rec {
   nativeBuildInputs = [ meson ninja pkgconfig ];
   buildInputs = [ glib vala ctpl libgee libsoup fcgi ];
 
-  meta = with stdenv.lib; {
+  meta = with lib; {
     homepage = "https://github.com/valum-framework/valum";
     description = "Web micro-framework written in Vala";
     license = licenses.lgpl3;