feat: add messaging transport rollout

.env.example

@@ -7,8 +7,6 @@ TREX_POSTGRESQL_DSN=dbname=trex_core host=/var/run/postgresql
 
 # --- Daemon (optional, defaults shown) ---
 TREX_TOTAL_SLOTS=10
-TREX_API_HOST=127.0.0.1
-TREX_API_PORT=8080
 # Background execution loop tick interval (seconds).
 TREX_EXECUTION_INTERVAL_SEC=1.0
 
@@ -38,3 +36,9 @@ TREX_PORTFOLIO_HUB_TOKEN=
 TREX_PORTFOLIO_HUB_TIMEOUT=5
 # Ledger outbox writer tick interval (seconds).
 TREX_LEDGER_INTERVAL_SEC=1.0
+
+# --- RabbitMQ transport (REQ-022, BAT-007) ---
+# trex-core ↔ 전략 모듈 통신은 RabbitMQ(AMQP) 메시지 기반 (HTTP /v1 API 는 제거됨).
+# 미설정이면 데몬은 InMemoryTransport stub 으로 기동(개발/CI 용; 전략과 통신 불가).
+TREX_RABBITMQ_URL=
+TREX_RABBITMQ_TIMEOUT=5