Pull Request Overview

Adds an opt-out mechanism (NuSealPackAssets) to allow disabling inclusion of build and buildTransitive assets in the produced package (Fixes #48).

• Wraps previously unconditional ItemGroups in a new Condition checking NuSealPackAssets != 'disable'.
• Extends the transitive assets ItemGroup condition to also require NuSealValidationScope == 'Transitive'.

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