Harden snapshot replay and integer powers

[Emma C (emmche)]

Filter snapshot commands before replay, handle full-range integer exponents safely, enable release control-flow protection, and add regression coverage.

Description of the changes:

• Hardened snapshot replay by filtering commands before execution and rejecting unsupported mode, memory, and arbitrary commands.
• Updated integer exponentiation to safely handle the full 32-bit range, including  INT32_MIN , without signed overflow or recursion.
• Enabled Control Flow Guard for Release builds and added native, managed, and UI regression coverage.

How changes were validated:

• Built and published the full solution for Release x64.
• Built the updated Calculator UI test project.
• Deployed the generated Calculator package and verified basic arithmetic.
• Exercised malicious snapshot payloads with and without expression state; both were rejected and left the display unchanged.