My Jetpack: add Search interstitial view

[retrofox]

• Changes the product status handling, checking if it requires a paid plan first of all.
• Adds the <SearchInterstitial /> component
• Register the /add-search route

Follow-up tasks

• Compute properly the price of Search 22702
• Register/reuse a new Jetpack redirect to lead to the checkout page 22701

Fixes #

Changes proposed in this Pull Request:

• My Jetpack: add Search interstitial view
• Intrdoduces status NEEDS_PURCHASE.

Jetpack product discussion

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

Testing instructions:

With a site without a Search product

• Go to My Jetpack
• Confirm you see the Add Search link in the product card

• Confirm you see the Search interstitial by clicking on the Add Search link

The checkout link is not already implemented :-(

• Buy the product from the jetpack dashboard
• Once you buy it, confirm you can activate/deactivate the Search product.

Screen.Recording.2022-02-04.at.6.38.03.PM.mov

[github-actions]

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[retrofox]

thanks