fix interoperability of all with hydra

Hydra add methods on Array.prototype which breaks the Array enumeration with for...in.
Use for...of instead
cf https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/for...of#difference_between_for...of_and_for...in for details on the issue

without this fix, it is impossible to use both `await initHydra()` and `all` in the same strudel code. Strudel errors with "Error: got "undefined" instead of pattern."

example code: https://strudel.cc/#YXdhaXQgaW5pdEh5ZHJhKCkKCmFsbChwaWFub3JvbGwpCgokOiBzKCJiZCIp

packages/core/repl.mjs

@@ -227,8 +227,8 @@ export function repl({
         pattern = eachTransform(pattern);
       }
       if (allTransforms.length) {
-        for (let i in allTransforms) {
-          pattern = allTransforms[i](pattern);
+        for (const transform of allTransforms) {
+          pattern = transform(pattern);
         }
       }