fix(OpenEnv): implement system-wide [0.1, 0.9] boundary scrub for Phase 2 compliance

fix(OpenEnv): global overhaul to high-resolution interior clamping (0.001-0.999) per technical diagnosis

fix(OpenEnv): implement robust grader bridge and strict interior clamping [0.1, 0.9] to satisfy Phase 2 validator

fix(OpenEnv): global overhaul to ensure every sub-score, reward, and model default is strictly within (0.01, 0.99) to satisfy Phase 2 validation

fix: add FastAPI REST endpoints for OpenEnv validator