fix: allow empty fieldNameSuffix in hashing mapper schema (#18367)

Author: dizel852

airbyte-webapp/src/components/connection/ConnectionForm/schemas/mapperSchema.ts

@@ -16,10 +16,16 @@ import {
 import { ToZodSchema } from "core/utils/zod";
 
 /**
- * Hashing
+ * Hashing mapper configuration schema
+ *
+ * Validates hashing mapper configurations for both regular and data activation connections.
+ *
+ * fieldNameSuffix: Appended to the field name after hashing (e.g., "_hashed" → "email_hashed")
+ *   - Regular connections: typically use non-empty suffix like "_hashed"
+ *   - Data activation connections: use empty string "" to allow mapper chaining on same field
  */
 export const hashingMapperConfiguration = z.object({
-  fieldNameSuffix: z.string().nonempty("form.empty.error"),
+  fieldNameSuffix: z.string(),
   method: z.nativeEnum(HashingMapperConfigurationMethod),
   targetField: z.string().nonempty("form.empty.error"),
 } satisfies ToZodSchema<HashingMapperConfiguration>);