new name for actions in Svelte 4.0

[ioucyf]

A suggestion to rename the element directive svelte:actions to differentiate them from sveltekit's <form> Actions, which in my opinion fits better with the latter than the former.

I think something like modifiers would express their purpose better than the current actions.

The usage would be the same.

<p use:modifier>
  Hello world!
</p>