chore: tidy up dynamic event handler generated code

[Rich-Harris]

Small tweak post-#12549 — we can make dynamic event handlers a bit more compact:

button.__click = function (...$$args) {
- const $$callback = a || b;
-
- return $$callback?.apply(this, $$args);
+ return (a || b)?.apply(this, $$args);
};

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Latest commit: 8a29715

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[brunnerh]

Please also see #12520 (comment)

[Rich-Harris]

This is orthogonal to that issue

[brunnerh]

Mainly wanted to preempt potential conflicts in case Dominic did some follow-up changes in response to my comment. Excuse my meddling 😅

[Rich-Harris]

All good — I wasn't aware of that side issue until you flagged it