Emit useful errors when encountering type 'any' in HCL

[chrisghill]

No description provided.

[Copilot]

Pull Request Overview

This PR enhances error reporting for HCL variables of type any (and empty types) and ensures hydration functions propagate informative errors.

• Added explicit checks for empty and any types in variableTypeStringToCtyType, with descriptive error messages.
• Refactored hydration helpers to return errors for unsupported/dynamic types and wrapped errors with contextual information.
• Updated tests to assert expected error messages for both top‐level and nested any scenarios and added corresponding test fixtures.

Comments suppressed due to low confidence (2)

pkg/opentofu/tofutoschema_test.go:20

• [nitpick] Consider adding a test case for an empty variable type to cover the new type cannot be empty error branch in variableTypeStringToCtyType.

	tests := []testData{

pkg/opentofu/tofutoschema.go:168

• This call duplicates the hydration already performed by hydrateArraySchema. Consider removing this second invocation and rely on hydrateArraySchema to initialize sch.Items before setting UniqueItems.

	return hydrateSchemaFromNameTypeAndDefaults(sch.Items, "", ty.ElementType(), getDefaultChildren(name, defaults))