exclude unused Redis auto-config (#6547)

fix(health): exclude unused Redis auto-config so default
/actuator/health stays UP

---

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app/core/src/main/resources/application.properties

@@ -93,6 +93,11 @@ posthog.host=https://eu.i.posthog.com
 
 spring.main.allow-bean-definition-overriding=true
 
+# spring-data-redis is on the classpath only for the optional Valkey backplane (which wires its own
+# factory); exclude Spring Boot's stock Redis auto-config so a default install doesn't create a dead
+# localhost:6379 factory that flips /actuator/health to DOWN.
+spring.autoconfigure.exclude=org.springframework.boot.data.redis.autoconfigure.DataRedisAutoConfiguration,org.springframework.boot.data.redis.autoconfigure.DataRedisReactiveAutoConfiguration
+
 # Set up a consistent temporary directory location
 java.io.tmpdir=${stirling.tempfiles.directory:${java.io.tmpdir}/stirling-pdf}