Execute a routed Tumbler quote

The route first claims an active quote with an ownership compare-and-set bound to a preallocated invocation ID. Concurrent/replayed consumers cannot produce a second debit, invocation, or provider dispatch, and execution uses the immutable quoted_price_usdc rather than a later listing price. Before any tUSDC debit, invocation row, or provider dispatch, governance evaluates tumbler.invoke with production cost=0, separate cost_tusdc, rail tumbler, and authoritative category, seller, and sandbox context. Agent status, rail, category, seller, attestation, sandbox, human-verification, and other nonfinancial constraints remain enforced. Caller-authored delegation is ignored. Production-USDC numeric caps alone do not block the zero-dollar attempt, and Tumbler creates no production spend reservation. Proven no-effect failures restore the quote only after confirming no invocation or charge evidence; ambiguous state remains consumed and non-retryable. On allow, the tUSDC debit and durable pending invocation commit atomically before provider dispatch. Commit-response ambiguity and every post-commit exception are resolved from exact invocation/payment evidence. Provider dispatch/response uncertainty, or finalization failure retains that evidence, issues no synthetic refund, and returns a reconciliation-required response without raw input. A later audit/lifecycle throw after exact durable success/settled truth reconstructs bounded success with the provider response body omitted. Successful execution returns a simulated receipt and the buyer's live lifecycle state, and also confirms the quote's choice-set snapshot (behavioral observability only; capture failures never affect the request). Reconciliation-held rows remain nonretryable; this tranche exposes no Tumbler reconciliation resolver endpoint.