Issues with head extension defer behavior

I've noticed that since the deferred scripts functionality was added, it doesn't fire htmx:head:before:add for them, so the user has no capability to prevent those tags from being added.

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The following has been evaluated and changing the behavior may have problematic consequences (see PR #4092). I'm recording it for posterity, but perhaps it can be ignored:

The defer detection doesn't detect module scripts properly. All modules are implicitly deferred, but this doesn't affect the defer JS property.

It reflects the defer attribute of the