Why

/feedback asks ThreadManager for the selected agent subtree before it uploads logs. The previous live subtree path reconstructed parent-child links by iterating every loaded thread and awaiting each thread config snapshot, so unrelated loaded-thread state could stall feedback subtree enumeration.

The loaded-thread set already belongs to ThreadManagerState. Reading thread-spawn parents from the captured CodexThread session sources at that boundary keeps unload and resume behavior manager-owned while avoiding per-session config inspection.

What Changed

• expose parent-child thread-spawn edges for loaded, non-internal threads from ThreadManagerState
• build the live child map from those edges while keeping agent metadata lookup and ordering in AgentControl
• add regression coverage for live subtree enumeration when no state DB is available

Validation

• git diff --check
• local Rust tests not run per request