Function recommend_hook_mode 

pub fn recommend_hook_mode(agent_key: &str) -> HookMode

Auto-detect the best hook mode for a given agent key based on its shell capabilities.

Criteria (verified against provider docs May 2026): Hybrid — MCP server (full Context OS) + shell hooks where available. Read/Search via MCP (reliable, cached). Shell via hooks (zero overhead). Mcp — agent has no reliable direct shell tool (e.g. IDE plugin only)