Premium Analytics: port the Sales by coupon widget

[nerrad]

Fixes: WOOA7S-1477

Proposed changes

• Ports the Sales by coupon widget into the Premium Analytics customizable dashboard.
• Registers the jpa/sales-by-coupon widget and renders the shared sales by coupon widget inside WidgetRoot using dashboard-level report params.
• Adds a Storybook dashboard story for the widget.
• Retargets the PR to trunk; the shared dashboard/package scaffolding is already present there, so this diff is limited to the Sales by coupon widget port.

Storybook screenshot

Captured from the local Storybook widget dashboard story.

Related product discussion/links

• WOOA7S-1477; parent WOOA7S-1457.
• Follows the widget port structure from Premium Analytics: port the Average items per order widget #49505.

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

No.

Testing instructions

• pnpm install --frozen-lockfile
• pnpm --filter @automattic/charts build
• pnpm --filter @automattic/number-formatters build
• pnpm --filter @automattic/jetpack-wp-build-polyfills build
• pnpm exec eslint projects/packages/premium-analytics/widgets/sales-by-coupon/render.tsx projects/packages/premium-analytics/widgets/sales-by-coupon/stories/sales-by-coupon-widget.stories.tsx projects/packages/premium-analytics/widgets/sales-by-coupon/widget.ts projects/packages/premium-analytics/widgets/stories/widget-dashboard-with-widget.tsx --max-warnings=0
• pnpm --filter @automattic/jetpack-premium-analytics typecheck
• pnpm --filter @automattic/jetpack-premium-analytics build
• pnpm --dir projects/js-packages/storybook run storybook:build
• Verified the Storybook story packages-premium-analytics-widgets-salesbycoupon--widget-dashboard-with-widget in a browser smoke test: title rendered, chart SVG rendered, coupon labels rendered, and no NaN/undefined output.

[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 🤖

---

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.

If you have questions about anything, reach out in #jetpack-developers for guidance!

[jp-launch-control]

Code Coverage Summary

This PR did not change code coverage!

That could be good or bad, depending on the situation. Everything covered before, and still is? Great! Nothing was covered before? Not so great. 🤷

Full summary · PHP report