fix(create-app): lit-element templates package.json

[patak-cat]

Description

Modify names in package.json of lit templates so they are unique and Jest stop issuing a warning.

Correct main and exports fields that were pointing to the wrong file, check vite.config.js of templates.

I don't know why we are generating a lib and not an app for lit templates. I imagine that the Lit team will switch these templates to an app when they update them to Lit 2.

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What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

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