[5.x] Revert requirement of prefixing attributes with :attr

[jasonvarga]

This PR essentially reverts #9576.

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We've changed the character from @ to \ in #9856 so that it's not a breaking change anymore. The change below is not needed.

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Now, the only thing you'll need to change is that if you have a parameter that starts with @. Since #8887, prefixing a parameter with @ will prevent parsing. You can get around this by prefixing with attr:, or using Vue/Alpine's alternate syntaxes:

{{ form:create
    in="contact"
-   @click="submitForm"
+   attr:@click="submitForm"
+   (or x-bind:click="submitForm")
}}

However! We're planning to change the syntax of #8887 so you won't even need to do that. Done!

[robdekort]

Neat. alt please :-)

[marcorieser]

preserveAspectRatio please

[dave-smyth]

loading please :)

[jeremyvienney]

styleattribute too please :)

[JonKaric]

Gonna end up with quite a few attributes on this list. I like not having to do attr: most of the time, but then it feels weird to have to type attr: for some and not for others and could confusing for someone just hopping into Statamic

{{ svg src="check" class="w-5 h-5 mr-2 fill-black" data-example="bacon" attr:x-show="selected.id == $id('select-option')" aria-hidden="true" }}

[jasonvarga]

Yeah still a bit derpy. Probably gonna revert to the old behavior. 👍