Fix All: Cleaned All Files

Fix restriction auto-lift, density-weighted penalty, /info endpoint accuracy, updated README

Fix: D0 seed above threshold, faster hospital drain, containment as primary metric

Fix treatment/recovery calibration, hospital breach reward, efficiency grader, recalibrate seeds

Fix speed score bug, restore partial resource replenishment, raise easy seed

Fix 1-step termination bug, fix done field in trajectory, recalibrate seeds

Fix core environment solvability: add treatment reduction, calibrate seeds and spread rates, fix hospital grader denominator

Add /grade endpoint, use real grader scores in evaluator

Initial submission: Cascade Containment