Added structured logging across services and repositories. Updated SQL queries to use parameterized placeholders for better readability and security. Enhanced error handling for external service communication.

backend/src/utils/logging.go

@@ -0,0 +1,29 @@
+package utils
+
+import (
+	"encoding/json"
+	"fmt"
+)
+
+const DefaultLogValueLimit = 4096
+
+func ToLogJSON(value any) string {
+	if value == nil {
+		return "null"
+	}
+
+	data, err := json.Marshal(value)
+	if err != nil {
+		return TruncateForLog(fmt.Sprintf("%+v", value), DefaultLogValueLimit)
+	}
+
+	return TruncateForLog(string(data), DefaultLogValueLimit)
+}
+
+func TruncateForLog(value string, limit int) string {
+	if limit <= 0 || len(value) <= limit {
+		return value
+	}
+
+	return value[:limit] + "...(truncated)"
+}