internal/rosa: create /bin symlinks via helper

This centralises the workaround for surprisingly common buggy scripts with nonstandard hardcoded paths.

Signed-off-by: Ophestra <cat@gensokyo.uk>

internal/rosa/package/x.az

@@ -781,6 +781,7 @@ package xwayland {
 		checksum = "0D0bs8EbDzlyLIULvm6lizqzdx4g1-umdbjVVO7zk-cS1kVIaSkKronCqj95tz-A";
 	};
 
+	bin = [ "bash" ];
 	exec = meson {
 		setup = {
 			"Dipv6": "false";
@@ -788,10 +789,6 @@ package xwayland {
 		};
 	};
 
-	early = `
-ln -sf ../system/bin/bash /bin/
-`;
-
 	inputs = [
 		bash,
 		gawk,