feat(auth): add email verification codes

- Add POST /auth/verification-code endpoint to email a code
- Store codes in Redis and verify them during registration
- Send verification emails asynchronously via Thymeleaf
- Replace email_verified column with code-based verification
- Group dependencies into version catalogue bundles

src/main/resources/application.yaml

@@ -30,6 +30,8 @@ spring:
   flyway:
     enabled: true
     baseline-on-migrate: true
+  thymeleaf:
+    enabled: false
 
 mybatis:
   configuration:
@@ -40,6 +42,8 @@ mybatis:
   mapper-locations: classpath:/mapper/*.xml
 
 logging:
+  pattern:
+    dateformat: dd MMM yyyy HH:mm:ss
   level:
     org.hibernate:
       orm.connections.pooling: off