Social: Register new CPT for Social Posts

[spsiddarthan]

Proposed changes:

• Added a new class Jetpack_Social_Note to register the custom post type
• I have added this class to the src folder of the plugin, but if need be it can be refactored into its own package in the future.
• I have used dashicons-welcome-write-blog as the menu icon for now, we can tweak this as well if need be.

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

pdrWKz-156-p2#comment-1932

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

Testing instructions:

• Add define( 'JETPACK_SOCIAL_NOTES_ENABLED', true ); to your wp-config.php. If you're on JN, install the code snippets plugin and copy define( 'JETPACK_SOCIAL_NOTES_ENABLED', true ); into it.
• Activate Jetpack Social on this branch
• Ensure you're able to see the new CPT Social Note in the sidebar of your wp-admin and you're able to create new Social Notes.
• Set JETPACK_SOCIAL_NOTES_ENABLED to false and ensure that you no longer see the new CPT in the sidebar.

[github-actions]

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Social plugin:

• Next scheduled release: March 5, 2024.
• Scheduled code freeze: February 26, 2024.

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[pablinos]

I think this is a good start! Just a couple of comments.

[pablinos]

I think we might want to add in some of the other labels for the type, and make them translated too. Some examples are in these comments

[spsiddarthan]

I have done this, Paul, let me know what you think

[pablinos]

I've noticed that on other types we're using hyphens rather than underscores in the post type slug/name. I don't know if that's a requirement or not!