Foresight Prediction Accuracy Tracker

Builds a complete prediction/decision journal: log predictions with a confidence level, resolve them later, and track real accuracy and calibration over time. Adds category accuracy breakdown, streak tracking, JSON export/import, and search/filtering beyond the proven-demand app this was modeled on. Fixed the genre's sneakiest bug — pending predictions diluting accuracy — via testing: 33 unit tests plus 3 real-UI runs, 0 errors. (AI-assisted, hand-verified.)