58e45d384e
Harvested from #2377 with thanks to @buko. Threads the parent MCP tool pool into child SubAgentRuntime construction and registers MCP-backed tools for child agents when MCP is enabled, while leaving the broader mention-browser/provider/config work for focused follow-ups. Validation: - cargo fmt --all -- --check - CARGO_TARGET_DIR=/Volumes/VIXinSSD/codewhale-pr2377-target cargo test -p codewhale-tui tools::subagent - CARGO_TARGET_DIR=/Volumes/VIXinSSD/codewhale-target/harvest-2377-recheck cargo test -p codewhale-tui tools::subagent --all-features