`[2026-07-13]` **WT #355 root-caused via ratatoskr telemetry (Vuong-routed via soong-dev).** The char-rp-reasoning turn-never-terminates wedge: over-budget `trim_messages` return (last-2 msgs + system + 8 bifrost tool schemas > input_budget = context_window×0.7) triggers the seat hang; worldtree confirmed + found the terminal-suppression (300s stall-watchdog cancel stuck in httpx `AsyncShieldCancellation`). Fix landing WT-side (Slice-C cancel-independent terminal). Two-proof localization (consumer-clean + tool-less-clean → WT-side tool-loop). Standing loop-in obligation on soong's next re-trigger.