Finalise OpenEnv submission: Clamp rewards to 0.0-1.0, update Gradio UI, and add Groq pipelines

3 fixes: README accurate, is_adversarial in state, reset(campaign_id) (100/100)

Appeal mechanic: is_adversarial + env.appeal() 2-turn flow (92/92 checks)

Fill easy GT gaps: full label×action coverage (79/79 checks)

Graduated severity penalty: sev-5→-0.30, sev-4→-0.15, sev-3→-0.05 (66/66)

Cross-post campaign mechanic: campaign_id in state, +0.15 escalate-all bonus (61/61 checks)

10 ambiguous hard scenarios + full valid_actions test suite (53/53 checks)

v2 docs & validation: README rewrite, openenv.yaml v2.0, validator 47/47