add booking flow

src/main/kotlin/com/android/trisolarisserver/repo/RoomStayChangeRepo.kt

@@ -0,0 +1,9 @@
+package com.android.trisolarisserver.repo
+
+import com.android.trisolarisserver.models.room.RoomStayChange
+import org.springframework.data.jpa.repository.JpaRepository
+import java.util.UUID
+
+interface RoomStayChangeRepo : JpaRepository<RoomStayChange, UUID> {
+    fun findByRoomStayIdAndIdempotencyKey(roomStayId: UUID, idempotencyKey: String): RoomStayChange?
+}

src/main/kotlin/com/android/trisolarisserver/repo/RoomStayRepo.kt

@@ -27,4 +27,24 @@ interface RoomStayRepo : JpaRepository<RoomStay, UUID> {
         @Param("fromAt") fromAt: java.time.OffsetDateTime,
         @Param("toAt") toAt: java.time.OffsetDateTime
     ): List<UUID>
+
+    @Query("""
+        select rs
+        from RoomStay rs
+        where rs.booking.id = :bookingId
+          and rs.toAt is null
+    """)
+    fun findActiveByBookingId(@Param("bookingId") bookingId: UUID): List<RoomStay>
+
+    @Query("""
+        select rs.room.id
+        from RoomStay rs
+        where rs.property.id = :propertyId
+          and rs.room.id in :roomIds
+          and rs.toAt is null
+    """)
+    fun findActiveRoomIds(
+        @Param("propertyId") propertyId: UUID,
+        @Param("roomIds") roomIds: List<UUID>
+    ): List<UUID>
 }