feature: support scoped slots

[xdom]

Fixes #107.

Looks like it was never really properly fixed.

Supports both variants:

<x-slot:name>
...
</x-slot>

<x-slot:name>
...
</x-slot:name>

Checklist

• deno check main/ to make sure the source code is fine
• deno lint main/ to utilise the linter. You could also do
  deno lint --fix main/ to automatically fix
• deno run generate ensure you include everything in the src/* - [ ] All
  tests pass in CI
• There are enough tests for the new fix/feature
• Grammar rules have not been renamed unless absolutely necessary (x rules
  renamed)
• The conflicts section hasn't grown too much (x new conflicts)
• The parser size hasn't grown too much (master: STATE_COUNT, PR:
  STATE_COUNT) >Check the value of STATE_COUNT in src/parser.c it should be
  roughly ~5k

[calebdw]

Looks like it's working:

[xdom]

To clarify, the original issue #107 requested that the parser supports a generic scoped slot closing tag </x-slot> instead of requiring a name-specific closing tag such as </x-slot:title>. This variant is also provided as an example in official Laravel docs.

Before:

After:

[calebdw]

Hmm, not sure I really care to support both variants---having the end tag match the start is better for consistency and readability

I'll leave it up to @EmranMR if he wants to support this

[EmranMR]

Fixes #107.
Looks like it was never really properly fixed.

Yup, technically, it should now be possible! but it requires messing about with the html c parser.

I will reopen the issue though, so it is tracked again, and definitely hit it in the future when I get a chance :)