Assume the role of the Secretary-General of a global economic council. Fusion energy has become commercially viable and infinitely cheap, leading to a post-scarcity potential in manufacturing and agriculture. Write a strategic roadmap outlining the transition of the global workforce, the redefinition of currency and value, and the management of geopolitical power shifts over the next 50 years. Identify the three most significant systemic risks to social stability during this transition and propose specific mitigation strategies for each.