Fix custom viewer integration

[carbonrobot]

• Move react to production deps so parcel can bundle them with the integration
• Move allotment css to file so tailwind can import them into the integration package

[changeset-bot[bot]]

🦋 Changeset detected

Latest commit: 5410545ebcea1bc3d54cd55b1e5b3e27708c7f74

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

This PR includes changesets to release 6 packages

| Name | Type | | -------------- | ----- | | @envyjs/webui | Patch | | @envyjs/apollo | Patch | | @envyjs/core | Patch | | @envyjs/nextjs | Patch | | @envyjs/node | Patch | | @envyjs/web | Patch |

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