Revamp Gradio app with Gradio 6, custom cybersecurity theme, and rich visualizations

Remove hackathon_env template, rewrite train.py for SentinelOpsArena

Implement Phase 3 (HTTP server) and Phase 4 (demo + Gradio app)

Implement Phase 2: environment core with MCPEnvironment base

Implement Phase 1: models, enterprise systems, attacks, rewards

Refine build plan with devil's advocate corrections

Add phased build plan and setup guide for SentinelOps Arena

Update SentinelOps Arena with detailed 14-hour implementation plan

Add SentinelOps Arena project specification

Initial project setup for OpenEnv Hackathon