PO-built prototype (FBM terrain, Whittaker biomes, procedural globe) with test body definitions for all planet types. Replaces pyplatec approach. Spike validates the pipeline architecture for batch #817. Includes handover doc, 9 test body definitions, and updated spike pipeline documentation. Stale pyplatec outputs removed. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>