Blocks: do not display block placeholder to non-admins

[jeherve]

Proposed changes:

We currently display a placeholder in the block editor when a block cannot be used because its associated module is not active. The placeholder offers a button inviting folks to activate the module.

Since only admins can activate modules, the placeholder is useless to non-admins. Let's consequently skip registering the blocks for non-admins when the associated module is not active.

Other information:

• Have you written new tests for your changes, if applicable?
• Have you checked the E2E test CI results, and verified that your changes do not break them?
• Have you tested your changes on WordPress.com, if applicable (if so, you'll see a generated comment below with a script to run)?

Jetpack product discussion

• N/A

Does this pull request change what data or activity we track or use?

• No

Testing instructions:

• Start with a site that's connected to WordPress.com.
• Create an additional user with an Author or Editor role.
• In Jetpack > Settings > Modules, deactivate all modules but blocks.
• Log in to the site as the author / editor
• Go to Posts > Add New
• Try to insert a Subcribe block by typing /subscribe
  • The block should not be available to be inserted.
  • You can repeat this with the other blocks touched by this PR:
    • Related Posts
    • Blog Stats
    • Top Posts
    • Ad block
• Open the Jetpack sidebar
  • You should not see the SEO, Sharing & Likes, or Publicize panels.
• Now log back in as the admin.
• Go to Posts > Add New
• Try to insert the blocks I mentioned above.
  • You should see all blocks as available.
  • Use the buttons in the placeholders to turn the feature on.
• Now log back in as the author / editor.
• Go to Posts > Add New
• Try to insert the blocks again
  • They should now be available to you.

[github-actions]

Are you an Automattician? Please test your changes on all WordPress.com environments to help mitigate accidental explosions.

• To test on WoA, go to the Plugins menu on a WordPress.com Simple site. Click on the "Upload" button and follow the upgrade flow to be able to upload, install, and activate the Jetpack Beta plugin. Once the plugin is active, go to Jetpack > Jetpack Beta, select your plugin, and enable the update/block-skeleton-non-admins branch.

• To test on Simple, run the following command on your sandbox:

  bin/jetpack-downloader test jetpack update/block-skeleton-non-admins
  

Interested in more tips and information?

• In your local development environment, use the jetpack rsync command to sync your changes to a WoA dev blog.
• Read more about our development workflow here: PCYsg-eg0-p2
• Figure out when your changes will be shipped to customers here: PCYsg-eg5-p2

[github-actions]

Thank you for your PR!

When contributing to Jetpack, we have a few suggestions that can help us test and review your patch:

• ✅ Include a description of your PR changes.
  
• ✅ Add a "[Status]" label (In Progress, Needs Team Review, ...).
  
• ✅ Add testing instructions.
  
• ✅ Specify whether this PR includes any changes to data or privacy.
  
• ✅ Add changelog entries to affected projects
  

This comment will be updated as you work on your PR and make changes. If you think that some of those checks are not needed for your PR, please explain why you think so. Thanks for cooperation 🤖

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The e2e test report can be found here. Please note that it can take a few minutes after the e2e tests checks are complete for the report to be available.

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Follow this PR Review Process:

1. Ensure all required checks appearing at the bottom of this PR are passing.
2. Choose a review path based on your changes:
   • A. Team Review: add the "[Status] Needs Team Review" label
     • For most changes, including minor cross-team impacts.
     • Example: Updating a team-specific component or a small change to a shared library.
   • B. Crew Review: add the "[Status] Needs Review" label
     • For significant changes to core functionality.
     • Example: Major updates to a shared library or complex features.
   • C. Both: Start with Team, then request Crew
     • For complex changes or when you need extra confidence.
     • Example: Refactor affecting multiple systems.
3. Get at least one approval before merging.

Still unsure? Reach out in #jetpack-developers for guidance!

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Jetpack plugin:

The Jetpack plugin has different release cadences depending on the platform:

• WordPress.com Simple releases happen semi-continuously (PCYsg-Jjm-p2).
• WoA releases happen weekly.
• Releases to self-hosted sites happen monthly. The next release is scheduled for none scheduled (scheduled code freeze on undefined).

If you have any questions about the release process, please ask in the #jetpack-releases channel on Slack.