move stuff to src folder, clarify readme

util.mjs

@@ -1,20 +0,0 @@
-// misc helpers
-
-import {execSync} from 'node:child_process';
-
-/**
- * terrible terrible terrible string diff helper for debugging
- * @param {string} a
- * @param {string} b
- */
-export function diff (a, b) {
-	// base64 input strings before passing to shell to avoid escaping issues
-	// https://stackoverflow.com/a/60221847
-	// also use `|| true` to not throw an error when `diff` returns non-zero
-	execSync(`bash -c '
-		diff --color -u <(echo ${btoa(a)} | base64 -d) <(echo ${btoa(b)} | base64 -d)
-	' || true`, {
-		// display result directly in terminal
-		stdio: 'inherit',
-	});
-}