Currently when a space is created its homepage is empty because there are no content blocks.

When a space is created:

• Add default blocks (Main Data, Metadata)

When a component is activated:

• Extend the suscess message:

  Component created successfully. You can add a content block for this component 
  in the home of the space. Go to [Landing page](url) to configure it.
  

@decidim/product please

1. confirm default blocks (should we consider a default block the Last activity, or Announcement?)

https://decidim-redesign.populate.tools/admin/participatory_processes/news/landing_page/edit

2. confirm the text of the message we would be showing