Enable Spring Boot Actuator with limited exposure and secure /actuator/mappings endpoint access.

backend/src/main/java/com/alttd/altitudeweb/config/SecurityConfig.java

@@ -56,6 +56,7 @@ public class SecurityConfig {
                         auth -> auth
                                 .requestMatchers(HttpMethod.OPTIONS, "/**").permitAll()
                                 .requestMatchers("/api/chat/send/**").access(allowedIpCheck)
+                                .requestMatchers("/actuator/mappings").access(allowedIpCheck)
                                 .requestMatchers("/api/form/**").authenticated()
                                 .requestMatchers("/api/login/getUsername").authenticated()
                                 .requestMatchers("/api/mail/**").authenticated()