Add admin controls for ambassador business rooms

[ethgr0wth]

Summary

• add redis-backed helpers for managing business room persistence and websocket teardown from the admin panel
• expose admin endpoints for creating, updating, deleting, and clearing business rooms with participant notifications
• extend the admin dashboard with a business management section and navigation link to edit room metadata

Testing

• python -m compileall ambassadors/fastapi-ambassador-leaderboard/main.py (fails: pyenv version 3.5.6 is not installed in this environment)

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https://chatgpt.com/codex/tasks/task_e_68f19b5370488333993d2c9fce5a93af