docs(be): Add comment explaining dialect removal

- Add comment explaining why hibernate.dialect was removed
- Hibernate 6.x auto-detects dialect from JDBC URL
- Explicit dialect configuration is deprecated

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Co-Authored-By: Claude <[email protected]>

Author: JIWONKIMS

src/main/resources/application-prod.yml

@@ -18,6 +18,7 @@ spring:
     properties:
       hibernate:
         format_sql: true
+        # dialect 설정 제거: Hibernate 6.x부터 JDBC URL 기반으로 자동 감지되며, 명시적 설정은 deprecated됨
 
   ai:
     vectorstore: