Fix missing validation for count and for-each meta-arguments

[liamcervante]

This PR fixes a crash that occurs when self-referencing direct instances from the count and for_each meta arguments. The same behaviour was also happening within the import blocks. These have been updated to share the same code path, and more extensive test cases have been added to cover the missing edge cases.

This had been partially fixed previously in #35407, but some edge-cases had been missed allowing certain conditions (direct instance references) to still trigger the panic.

Fixes #35427

Target Release

1.9.2

Draft CHANGELOG entry

BUG FIXES

• Fix panic when self-referencing direct instances from count and for_each meta arguments.

[github-actions]

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[github-actions]

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