Add future.v7_fetcherPersist flag

[brophdawg11]

Dependent on #10961

Implemented the new fetcher persist/cleanup behavior behind a new future.v7_fetcherPersist flag in the router.

• Implements the updated version of 🗺️ fetcher, submit, and Form Changes remix#7698
• 3rd and final PR to supersede Add support for fetcher key specification and persistence #10945

[changeset-bot]

🦋 Changeset detected

Latest commit: 546ea91

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 5 packages

Name	Type
@remix-run/router	Minor
react-router	Patch
react-router-dom	Patch
react-router-dom-v5-compat	Patch
react-router-native	Patch

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[github-actions]

🤖 Hello there,

We just published version 6.18.0-pre.0 which includes this pull request. If you'd like to take it for a test run please try it out and let us know what you think!

Thanks!

[github-actions]

🤖 Hello there,

We just published version 6.18.0 which includes this pull request. If you'd like to take it for a test run please try it out and let us know what you think!

Thanks!