Fix timestamp serialization to ISO-8601 format instead of array format

Co-authored-by: dmccoystephenson <21204351+dmccoystephenson@users.noreply.github.com>

Author: Copilot

backend/src/main/java/com/accord/config/JacksonConfig.java

@@ -0,0 +1,26 @@
+package com.accord.config;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.SerializationFeature;
+import com.fasterxml.jackson.datatype.jsr310.JavaTimeModule;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Primary;
+
+/**
+ * Jackson configuration to properly serialize Java 8 date/time types
+ */
+@Configuration
+public class JacksonConfig {
+
+    @Bean
+    @Primary
+    public ObjectMapper objectMapper() {
+        ObjectMapper mapper = new ObjectMapper();
+        // Register JavaTimeModule to handle Java 8 date/time types
+        mapper.registerModule(new JavaTimeModule());
+        // Serialize dates as ISO-8601 strings instead of arrays
+        mapper.disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS);
+        return mapper;
+    }
+}