Compose Semuta with completed paid Box discard

docs/SEMUTA_SOURCE_UPDATE_20260907.md

@@ -63,17 +63,18 @@ Do not ask again about normal targets, forced-discard owner bookkeeping, simulta
 
 The explicit `semuta` development profile starts a fresh Richese roster
 without opening ordinary expansion starts. It now interrupts **one public
-ordinary-card discard** from a clean transaction with a neutral
-fresh-discard opportunity for every seat, regardless of hidden Semuta
+ordinary-card discard or the used Box after a completed paid Nullentropy
+search**, provided the parent transaction is clean, with a neutral
+fresh-discard opportunity for every seat regardless of hidden Semuta
 possession. Each seat can Continue; only the canonical holder with a
 free hand slot and a card discarded by another player can commit. The
 sole eligible fresh card transfers automatically in the same accepted
 action, then Semuta goes to the normal discard pile. The saved ordinary
-card effect resumes once; passing by every seat preserves the original
-discard and effect. No face from an undisclosed event is projected before
-commitment. Owner-only multi-candidate selection support exists in the
-reaction component and bot adapter, but no multi-discard producer is
-activated in this first boundary.
+card effect or Box parent resumes once; passing by every seat preserves
+the original discard and effect. No face from an undisclosed event is
+projected before commitment. Owner-only multi-candidate selection
+support exists in the reaction component and bot adapter, but no
+multi-discard producer is activated in this bounded runtime.
 
 This neutral all-seat acknowledgement is a conservative **application
 policy**, not a newly discovered publisher timing rule. The explicit
@@ -81,7 +82,9 @@ free-slot requirement is a provisional safety guard, not the printed
 resolution of full-hand take-before-discard. Auction, CHOAM market,
 pending gifts, competing responses and other typed discard producers
 retain their existing automatic continuation; Semuta cannot claim those
-events yet. No source ruling is inferred from this omission. The
+events yet. The completed Box's selected search card stays private and
+its paid shuffle is not repeated when another seat takes the used Box.
+No source ruling is inferred from this omission. The
 separate [reaction privacy audit](SEMUTA_PRIVACY_REVIEW.md) explains why
 auto-closing only when nobody secretly holds the card would leak
 possession. The main game and public expansion gates remain closed.