(PoC) Forms: Migrate dashboard routing to TanStack Router

[lezama]

Proof of concept migration from React Router v7 to TanStack Router.

DO NOT MERGE

Changes:

• Replace React Router v7 with TanStack Router v1
• Update navigate() calls to use TanStack Router API
• Add @ts-expect-error annotations for strictNullChecks requirement

Testing instructions:

• Build and test Forms dashboard routing functionality

[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 or WordPress.com Site Helper), and enable the add/forms-tanstack-router branch.
• To test on Simple, run the following command on your sandbox:

bin/jetpack-downloader test jetpack add/forms-tanstack-router

bin/jetpack-downloader test jetpack-mu-wpcom-plugin add/forms-tanstack-router

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]

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[jp-launch-control]

Code Coverage Summary

Cannot generate coverage summary while tests are failing. 🤐

Please fix the tests, or re-run the Code coverage job if it was something being flaky.

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