fix(api): disable mail health indicator in docker profile

Backend now starts and Flyway migrations run, but /actuator/health returned
503 (DOWN) so Docker marked the container unhealthy and the frontend refused
to start. Cause: spring-boot-starter-mail registers a mail health indicator
that tries to connect to localhost:1025; there is no SMTP container in this
deployment, so it reports DOWN and drags the aggregate health to DOWN.

Disable the mail health indicator in the docker profile. Mail being down must
not make the whole service unhealthy in an SMTP-less deployment.

cannamanage-api/src/main/resources/application-docker.properties

@@ -13,6 +13,9 @@ cannamanage.security.jwt.secret=${CANNAMANAGE_SECURITY_JWT_SECRET}
 # Actuator
 management.endpoints.web.exposure.include=health
 management.endpoint.health.show-details=never
+# No SMTP container in this deployment — don't let the mail health indicator
+# drag /actuator/health to DOWN (503), which would mark the container unhealthy.
+management.health.mail.enabled=false
 
 # Disable mail in Docker (no SMTP container)
 spring.mail.host=localhost