integrate-arcjet-guard-crewailisted

# Integrate Arcjet Guard into CrewAI `arcjet.guard.crewai` wraps the agent's existing Arcjet client. It never talks to the Arcjet API itself. Shared Guard fundamentals (client, rules, labels, decisions, capture, registration) live in [../arcjet/references/guards_python.md](../arcjet/references/guards_python.md). Load that reference for anything that is not CrewAI-specific. Official `crewai` only — not community forks, not LangChain Crew wrappers, not an npm CrewAI port. There is **no** `arcjet[crewai]` extra: CrewAI hard-depends on `chromadb`, which carries unpatched RCE CVE-2026-45829, so an Arcjet extra must not pull it in. Install CrewAI yourself. Importing `arcjet.guard.crewai` does not load LangChain. Exports: `register_arcjet_hooks`, `unregister_arcjet_hooks`, `ArcjetCrewAIHooks`, `guard_tool`, `ToolPolicy`, `sanitize_tool_name`, `free_text_arguments`. There is no `guard_crew`. Two surfaces, one decision rule: - **A tool a crew, LiteAgent, MCP adapter, or crew-injected list executes** → `register_arcjet_hooks` + `ToolPolicy`. Gate is process-wide `PRE_TOOL_CALL` only. DENY raises `HookAborted(reason=..., source="arcjet")`. - **A CrewAI `BaseTool` you call yourself** → `guard_tool`. This is the **only** CrewAI path that raises `ArcjetDeniedError` / `ArcjetUnavailableError`. `BaseTool.run` never dispatches `PRE_TOOL_CALL`. Docs: https://docs.arcjet.com/guards/crewai/. ## The gate is process-wide `PRE_TOOL_CALL`, once `register_arcjet_hooks` registers on