Enforce calling create method in JS SDK

[jakubno]

This prevents to accidentally use new Sandbox(), which doesn't initialize Sandbox class correctly

[changeset-bot[bot]]

🦋 Changeset detected

Latest commit: ca466f81f6f221b59bbe4068718c9195779dfc1e

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

This PR includes changesets to release 1 package

| Name | Type | | ---- | ----- | | e2b | Patch |

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