Simplify ComponentFactory property injection and add subtype validation tests

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Remove redundant conditional and validate subtype property injection

Description

Addresses feedback from #64595 to simplify property injection logic and ensure correctness when component activators return subtypes.

Code simplification

• Removed redundant if-else in ComponentFactory.InstantiateComponent that had identical behavior in both branches
• Both paths called the property activator with the actual component type, making the conditional check unnecessary

Test coverage

• Added InstantiateComponent_WhenActivatorReturnsSubtype_InjectsAllSubtypeProperties - validates base and derived type properties are injected when activator returns a subtype
• Added InstantiateComponent_WhenActivatorReturnsExactType_InjectsPropertiesIdenticallyToSubtype - confirms behavior is identical regardless of type matching
• Updated existing test to verify derived type properties with [Inject] attribute

All 22 tests pass.

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