Explain the mechanics of Shor's Algorithm and its specific threat to RSA-2048 encryption to a Board of Directors that has a background in finance, not computer science. Your explanation must cover: 1) Why classical computers cannot break RSA efficiently, 2) How quantum superposition and entanglement change the calculation complexity, and 3) The difference between Quantum Key Distribution (QKD) and Post-Quantum Cryptography (PQC). Conclude with a recommended 5-year budget allocation for transitioning the company's infrastructure to be quantum-safe.