feat: tighten EscalationROI, add ambiguous medium case, LLM note judge wrapper

refactor: tighten rubric discrimination + LLM path + add running doc

refactor: update difficulty levels and enhance scoring rubrics in documentation and code

refactor: build grading on OpenEnv Rubric system

docs: sync AGENT.md and README with current grading values, add LICENSE

feat: harden grading, expand task catalog, add episode persistence

fix: update OpenEnv link in AGENT.md documentation

Enhance chargeback dispute handling system with improved architecture and decision-making processes