Description

The theme export process already removes theme slugs from template parts, as when templates come from files these aren't needed. Similarly we should remove other site/implementation specific details from templates on export, including:

• Removed the ref id on the Navigation block
• Remove IDs from the image block
• Remove IDs from the query block

There may be more like this that we need to remove.

Step-by-step reproduction instructions

1. Add some items to the navigation block in your theme
2. Export your theme using the site editor
3. You will see a "ref id" in the template for the navigation block - this won't have any meaning on another site.

Screenshots, screen recording, code snippet

No response

Environment info

No response

Please confirm that you have searched existing issues in the repo.

Yes

Please confirm that you have tested with all plugins deactivated except Gutenberg.

Yes