feat: promote accepted proposals from API

server/store/match_sql.go

@@ -63,6 +63,44 @@ const AcceptedMatchParticipantInsertSQL = `INSERT INTO match_participants
     (match_id, player_id, ticket_id, slot, team)
 VALUES ($1, $2, $3, $4, $5)`
 
+const StoredProposalMatchPlanSQL = `SELECT match_region, match_protocol
+FROM proposals
+WHERE proposal_id = $1 AND state = 'ACCEPTED'`
+
+const StoredProposalMatchPlayersSQL = `SELECT player_id, team, slot
+FROM proposal_participants
+WHERE proposal_id = $1 AND response = 'ACCEPTED'
+ORDER BY player_id`
+
+// PromoteStoredAcceptedProposal materializes the exact topology persisted by
+// the matcher once every player has accepted. The deterministic match ID makes
+// a request retry converge after an API/worker interruption.
+func PromoteStoredAcceptedProposal(ctx context.Context, db *sql.DB, proposalID string, now time.Time) error {
+	if db == nil || proposalID == "" || now.IsZero() {
+		return fmt.Errorf("invalid stored proposal promotion arguments")
+	}
+	plan := AcceptedMatchPlan{MatchID: "match-" + proposalID, ProposalID: proposalID}
+	if err := db.QueryRowContext(ctx, StoredProposalMatchPlanSQL, proposalID).Scan(&plan.Region, &plan.Protocol); err != nil {
+		return err
+	}
+	rows, err := db.QueryContext(ctx, StoredProposalMatchPlayersSQL, proposalID)
+	if err != nil {
+		return err
+	}
+	defer rows.Close()
+	for rows.Next() {
+		var player MatchPlayer
+		if err := rows.Scan(&player.PlayerID, &player.Team, &player.Slot); err != nil {
+			return err
+		}
+		plan.Players = append(plan.Players, player)
+	}
+	if err := rows.Err(); err != nil {
+		return err
+	}
+	return CreateMatchFromAcceptedProposal(ctx, db, plan, now)
+}
+
 // CreateMatchFromAcceptedProposal atomically promotes the exact accepted
 // roster into an ALLOCATING match. An existing match ID is an idempotent retry
 // only if every durable field and participant assignment matches the request.