Add JWT auth with per-user data isolation and account settings.

Users can register, log in, and manage profile/password in a personal account page; server data is scoped by owner across contacts, maps, tags, and import.

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/core/auth_views.py

@@ -0,0 +1,66 @@
+from rest_framework import status
+from rest_framework.permissions import AllowAny, IsAuthenticated
+from rest_framework.response import Response
+from rest_framework.views import APIView
+from rest_framework_simplejwt.tokens import RefreshToken
+
+from contacts.bootstrap import ensure_user_defaults
+from core.drf_mixins import JwtAuthMixin
+from .auth_serializers import (
+    ChangePasswordSerializer,
+    RegisterSerializer,
+    UpdateProfileSerializer,
+    UserSerializer,
+)
+
+
+def tokens_for_user(user):
+    refresh = RefreshToken.for_user(user)
+    return {
+        'refresh': str(refresh),
+        'access': str(refresh.access_token),
+        'user': UserSerializer(user).data,
+    }
+
+
+class RegisterView(JwtAuthMixin, APIView):
+    def get_permissions(self):
+        return [AllowAny()]
+
+    def post(self, request):
+        serializer = RegisterSerializer(data=request.data)
+        serializer.is_valid(raise_exception=True)
+        user = serializer.save()
+        ensure_user_defaults(user)
+        return Response(tokens_for_user(user), status=status.HTTP_201_CREATED)
+
+
+class MeView(JwtAuthMixin, APIView):
+    def get_permissions(self):
+        return [IsAuthenticated()]
+
+    def get(self, request):
+        return Response(UserSerializer(request.user).data)
+
+    def patch(self, request):
+        serializer = UpdateProfileSerializer(
+            data=request.data,
+            context={'request': request},
+        )
+        serializer.is_valid(raise_exception=True)
+        user = serializer.save()
+        return Response(UserSerializer(user).data)
+
+
+class ChangePasswordView(JwtAuthMixin, APIView):
+    def get_permissions(self):
+        return [IsAuthenticated()]
+
+    def post(self, request):
+        serializer = ChangePasswordSerializer(
+            data=request.data,
+            context={'request': request},
+        )
+        serializer.is_valid(raise_exception=True)
+        serializer.save()
+        return Response({'detail': 'Пароль изменён.'})