Forms: Finalize documentation and changelog

[enejb]

Fixes #

Proposed changes

• Add "Building the Plugin" section to custom fields documentation with build instructions, output file reference table, and development workflow guidance
• Add complete emoji rating field example to the list of working examples in docs
• Add @babel/runtime as a required dependency in the example package.json template
• Add Jetpack plugin changelog entry for the custom fields feature

Other information

This is PR 5/5 (final) in a stacked PR series, based on #47930. The full stack:

1. PR Forms: Add PHP foundation for custom field extensibility #47931 — Forms: PHP foundation for custom field registry
2. PR Forms: Add JavaScript Field API for editor integration #47932 — Forms: JS/Editor API for custom field blocks
3. PR Forms: Add label support, dashboard hooks, and Interactivity API #47933 — Forms: Label, dashboard rendering, and Interactivity API
4. PR Forms: Add asset pipeline and style support for custom fields #47930 — Forms: Asset pipeline and style support
5. PR Forms: Finalize documentation and changelog #47929 — Forms: Documentation and changelog (this PR)

• Generate changelog entries for this PR (using AI).

Related product discussion/links

• Custom fields documentation: projects/packages/forms/docs/custom-fields.md

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

No.

Testing instructions

• Review projects/packages/forms/docs/custom-fields.md and verify the new "Building the Plugin" section renders correctly and the build output table is accurate
• Verify the emoji rating field example is listed alongside the existing NPS and color picker examples
• Confirm the @babel/runtime dependency addition in the example package.json is correct
• Review the changelog entry in projects/plugins/jetpack/changelog/add-form-fields-programatically

[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 WoA dev 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 (Jetpack), and enable the add/form-fields-docs-changelog branch.
• To test on Simple, run the following command on your sandbox:

bin/jetpack-downloader test jetpack add/form-fields-docs-changelog

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 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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🔴 Action required: Please add missing changelog entries for the following projects: projects/packages/forms

Use the Jetpack CLI tool to generate changelog entries by running the following command: jetpack changelog add.
Alternatively, you can check the "Generate changelog entries" checkbox in the PR description to have them auto-generated.
Guidelines: /docs/writing-a-good-changelog-entry.md

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Follow this PR Review Process:

1. Ensure all required checks appearing at the bottom of this PR are passing.
2. Make sure to test your changes on all platforms that it applies to. You're responsible for the quality of the code you ship.
3. You can use GitHub's Reviewers functionality to request a review.
4. When it's reviewed and merged, you will be pinged in Slack to deploy the changes to WordPress.com simple once the build is done.

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Jetpack plugin:

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

[jp-launch-control]

Code Coverage Summary

No summary data is available for parent commit 004216f, so cannot calculate coverage changes. 😴

If that commit is a feature branch rather than a trunk commit, this is expected. Otherwise, this should be updated once coverage for 004216f is available.

Full summary · PHP report · JS report