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/tools/text/diffstat/default.nix

@@ -1,4 +1,4 @@
-{ fetchurl, stdenv }:
+{ fetchurl, lib, stdenv }:
 
 stdenv.mkDerivation rec {
   name = "diffstat-1.63";
@@ -11,7 +11,7 @@ stdenv.mkDerivation rec {
     sha256 = "0vyw200s5dv1257pmrh6c6fdkmw3slyz5szpqfx916xr04sdbpby";
   };
 
-  meta = with stdenv.lib; {
+  meta = with lib; {
     description = "Read output of diff and display a histogram of the changes";
     longDescription = ''
       diffstat reads the output of diff and displays a histogram of the