v0.0.25 | KVM 서버 관리 API 추가

- KVMServer 모델 추가 (멀티 서버 지원)
- 서버별 SSH 키 암호화 저장
- msa-django-libvirt 연동용 SSH 정보 조회 API

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

users/serializers.py

@@ -1,5 +1,5 @@
 from rest_framework import serializers
-from .models import CustomUser
+from .models import CustomUser, KVMServer
 from rest_framework_simplejwt.serializers import TokenObtainPairSerializer
 from rest_framework.exceptions import ValidationError
 
@@ -86,3 +86,60 @@ class CustomTokenObtainPairSerializer(TokenObtainPairSerializer):
         data["email"] = user.email
         data["grade"] = user.grade
         return data
+
+
+class KVMServerSerializer(serializers.ModelSerializer):
+    """KVM 서버 시리얼라이저"""
+    tags_list = serializers.ListField(
+        child=serializers.CharField(),
+        required=False,
+        write_only=True
+    )
+    private_key = serializers.CharField(write_only=True, required=False)
+
+    class Meta:
+        model = KVMServer
+        fields = [
+            'id', 'name', 'host', 'port', 'username',
+            'encrypted_private_key_name', 'libvirt_uri',
+            'description', 'tags', 'tags_list', 'is_active',
+            'last_used_at', 'created_at', 'updated_at', 'private_key'
+        ]
+        read_only_fields = ['id', 'last_used_at', 'created_at', 'updated_at']
+        extra_kwargs = {
+            'tags': {'required': False},
+        }
+
+    def to_representation(self, instance):
+        data = super().to_representation(instance)
+        data['has_ssh_key'] = bool(instance.encrypted_private_key)
+        data['tags_list'] = instance.get_tags_list()
+        return data
+
+    def create(self, validated_data):
+        tags_list = validated_data.pop('tags_list', None)
+        private_key = validated_data.pop('private_key', None)
+
+        instance = super().create(validated_data)
+
+        if tags_list is not None:
+            instance.set_tags_list(tags_list)
+        if private_key:
+            instance.save_ssh_key(private_key, validated_data.get('encrypted_private_key_name'))
+        instance.save()
+
+        return instance
+
+    def update(self, instance, validated_data):
+        tags_list = validated_data.pop('tags_list', None)
+        private_key = validated_data.pop('private_key', None)
+
+        instance = super().update(instance, validated_data)
+
+        if tags_list is not None:
+            instance.set_tags_list(tags_list)
+            instance.save()
+        if private_key:
+            instance.save_ssh_key(private_key, validated_data.get('encrypted_private_key_name'))
+
+        return instance