patchShebang breaks scripts on macOS

[tristanpemble]

the default patchShebang functionality ends up with non-functional scripts on macOS:

./result/bin/composer: line 2: ?php: No such file or directory
./result/bin/composer: line 4: syntax error near unexpected token `{'
./result/bin/composer: line 4: `if (PHP_SAPI !== 'cli' && PHP_SAPI !== 'phpdbg') {'

relevant NixOS/nixpkgs#2146, NixOS/nixpkgs#23018

it seems most PHP derivations handle this on their own (e.g. NixOS/nixpkgs#87406)

is this something that can/should be handled by composer2nix?