Add metadata.schema.json to all SDDS component YAMLs

I have just learned that instead of:

'$schema': 'https://git.drupalcode.org/project/sdc/-/raw/1.x/src/metadata.schema.json'

we should use:

https://git.drupalcode.org/project/drupal/-/raw/HEAD/core/assets/schemas/v1/metadata.schema.json

yet XB isn't using that yet. Updating summary with the correct one.

Updated summary to point to the one example that uses the core schema:

https://git.drupalcode.org/project/experience_builder/-/blob/0.x/compone...

Related issue:

📌 Update components to use core metadata.schema.json instead of old SDC module one Active

This was done as part of:

📌 Update SDDS SDCs attributes prop to align with XB Fixed

kristen pol → credited anand.toshniwal93 → .

kristen pol → credited jacobadeutsch → .

Note that I'm seeing that some of the XB ones don't use the single quotes around them and some do, but we can leave it with the quotes.

Merged via:

📌 Update SDDS SDCs attributes prop to align with XB Fixed

Automatically closed - issue fixed for 2 weeks with no activity.