feat: add multi-image vision analysis

apps/api/serializers.py

@@ -50,6 +50,38 @@ class GenerateImageRequestSerializer(serializers.Serializer):
     parameters = serializers.DictField(required=False, default=dict)
 
 
+class VisionImageInputSerializer(serializers.Serializer):
+    image_url = serializers.URLField(required=False, allow_blank=True)
+    image_base64 = serializers.CharField(required=False, allow_blank=True)
+
+    def validate(self, attrs):
+        has_url = bool(str(attrs.get("image_url") or "").strip())
+        has_base64 = bool(str(attrs.get("image_base64") or "").strip())
+        if has_url == has_base64:
+            raise serializers.ValidationError(
+                "每张图片必须且只能提供 image_url 或 image_base64。"
+            )
+        return attrs
+
+
+class AnalyzeImagesRequestSerializer(serializers.Serializer):
+    prompt = serializers.CharField(trim_whitespace=True, allow_blank=False)
+    model = serializers.CharField(
+        required=False,
+        allow_blank=True,
+        trim_whitespace=True,
+        max_length=64,
+    )
+    images = VisionImageInputSerializer(many=True, allow_empty=False)
+    parameters = serializers.DictField(required=False, default=dict)
+
+    def validate_images(self, value):
+        max_images = max(1, int(settings.VISION_MAX_IMAGES))
+        if len(value) > max_images:
+            raise serializers.ValidationError(f"单次最多上传 {max_images} 张图片。")
+        return value
+
+
 class RechargeCreateRequestSerializer(serializers.Serializer):
     amount = serializers.DecimalField(
         max_digits=12,