Refine comment wording for scoring stability paths

Clamp grader and inference rewards securely to 0.01 and 0.99

Fix inference stdout formatting and update graders tests for strictly clamped reward constraint bounds

fix: entirely purge all occurrences of zeros and ones to guarantee 0.01 and 0.99 minimum fallbacks

fix: global invariant enforcement 0<score<1 on api pit stop and robust tests

fix: add root endpoint so base URL returns welcome JSON instead of 404

feat: v2.0 — fraud detection task, severity grading, investigation mode, security hardening, 78 tests

fix: make reset body optional for empty POST

fixed validation