[10.x] Fix kebab-case attributes not passed to children component data

[aguingand]

Fixes #48956.

Today, when doing <x-test {{ $attributes }} />, kebab-cased attributes are ignored (for component class constructor parameters and anonymous component @props)

Class components

For compiled class components I have added ->toProps() to attributes array which convert attribute names to camelCase (diff). Kebab-case attributes are now passed to component constructor parameters. I have updated a test case to assert the data passed to Component::resolve() method.

Anonymous components

For anonymous components I have updated the data() method to transform attributes name to camelCase. I have added a test case for this method.

Attributes cleaning

In compiled component tags, I changed except() to exceptProps() to remove kebab-case attributes based on component constructor parameters (diff). I have updated a test case with user-id instead of userId to ensure kebab-case attributes are removed.

Naming considerations

The new ComponentAttributeBag::toProps() method may be not explicit enough, I can rename it if needed.

[taylorotwell]

See my comment here: #48956

I'm afraid this will break all sorts of other use cases people may already be doing.

[aguingand]

@taylorotwell Noted. I submitted this PR because it looked like a needed fix for the "attributes spread" feature.
Related PRs :

• [8.x] Fix attribute nesting on anonymous components #36240
• [9.x] Support for overriding component props using attributes spread #35742