Design Tr Module From Intent

Design both chains and the shared front end, then compute the budgets.

The sibling of the route above, not a widening of it. POST /api/tr-module is the pure-engine path and needs an isolation figure and a limiter the caller has already chosen; a caller who only knows "9.4 GHz, 20 W" has neither, which is exactly the design intent this route serves.

Selection and orchestration reuse assemble_tr_module, the SAME function the design_tr_module agent tool calls, so the assistant and any UI can never disagree about which part fills a slot.

Rate-limited harder than either sibling (15/min vs 60): this one runs the full transmit convergence loop, the receive assembler and the per-slot scoring agents against the component database.