Allow <.input type="checkbox"> without value attr in core components

[gorghoa]

Hi!

Currently, the <.input type="checkbox"> in the core components is "unsafe" to use from a DX point of view:

Using <.input type="checkbox" checked={true} /> without an attribute value="…" raises a runtime exception because the value key is not in assigns.

The @value is not a required attr in the def input, yet, the def input for checkbox was pattern matching for it in the function argument, so the value attr is de facto required even if announced optional.

I can’t see why the value is mandatory, the body of the function is barely using it as a fallback if @checked is not set. So I propose to just dropping it from the function pattern matching, and later check if present in the assigns map.

See also this discussion I started on elixir forum before making this PR.

Thanks for your kind review 🙏 !

[Gazler]

Thanks <3