create-svelte: set folder name as pkg.name

[ambarvm]

Fixes #2050

Use name of folder as name in package.json. If folder name is not a valid package name, it is converted to a valid name by removing and replacing invalid characters.

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Latest commit: 6bb7c67

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

This PR includes changesets to release 1 package

Name	Type
create-svelte	Patch

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