过滤图片编辑响应中的空图像数据

忽略上游返回的空 b64_json 条目，避免把空字符串转发为图像结果。

新增空条目与有效条目混合响应的回归测试。

server-rs/crates/platform-image/src/vector_engine/raw_edit.rs

@@ -264,11 +264,7 @@ pub async fn create_vector_engine_raw_image_edit(
             });
         }
     };
-    let b64_images = payload
-        .data
-        .into_iter()
-        .map(|entry| entry.b64_json)
-        .collect::<Vec<_>>();
+    let b64_images = collect_b64_images(payload.data);
     if b64_images.is_empty() {
         let message = format!("{failure_context}：上游未返回 b64_json 图片");
         let audit = build_failure_audit(
@@ -299,6 +295,13 @@ pub async fn create_vector_engine_raw_image_edit(
     })
 }
 
+fn collect_b64_images(data: Vec<RawImageEditResponseEntry>) -> Vec<String> {
+    data.into_iter()
+        .map(|entry| entry.b64_json)
+        .filter(|value| !value.is_empty())
+        .collect()
+}
+
 fn invalid_request(context: &str, message: String) -> PlatformImageError {
     PlatformImageError::InvalidRequest {
         provider: VECTOR_ENGINE_PROVIDER,
@@ -415,6 +418,16 @@ mod tests {
         assert!(serde_json::from_str::<RawImageEditResponsePayload>(r#"{"data":[{}]}"#).is_err());
     }
 
+    #[test]
+    fn raw_success_response_discards_empty_b64_json_entries() {
+        let payload: RawImageEditResponsePayload = serde_json::from_str(
+            r#"{"data":[{"b64_json":""},{"b64_json":"valid"}]}"#,
+        )
+        .expect("response envelope");
+
+        assert_eq!(collect_b64_images(payload.data), vec!["valid"]);
+    }
+
     #[test]
     fn raw_image_edit_dimensions_enforce_strict_contract() {
         assert!(validate_raw_image_edit_dimensions(1024, 640).is_ok());