feat: allow configuring multiple openapi servers

backend/src/main/java/com/openisle/config/SpringDocProperties.java

@@ -0,0 +1,20 @@
+package com.openisle.config;
+
+import java.util.ArrayList;
+import java.util.List;
+import lombok.Data;
+import org.springframework.boot.context.properties.ConfigurationProperties;
+import org.springframework.stereotype.Component;
+
+@Data
+@Component
+@ConfigurationProperties(prefix = "springdoc.api-docs")
+public class SpringDocProperties {
+    private List<ServerConfig> servers = new ArrayList<>();
+
+    @Data
+    public static class ServerConfig {
+        private String url;
+        private String description;
+    }
+}