[fix] harden migration around imports

[dummdidumm]

harden declared logic around imports:

• remove type only load imports
• handle imports with same name as load exports
• bail on export * from ..
• handle undefined declared map.

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Latest commit: cba3de2

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

This PR includes changesets to release 1 package

Name	Type
svelte-migrate	Patch

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