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/contacts/models.py

@@ -1,3 +1,4 @@
+from django.conf import settings
 from django.core.validators import MaxValueValidator, MinValueValidator
 from django.db import models
 
@@ -10,6 +11,14 @@ from core.choices import (
 class Contact(models.Model):
     """Контакт в социальном графе."""
 
+    owner = models.ForeignKey(
+        settings.AUTH_USER_MODEL,
+        on_delete=models.CASCADE,
+        related_name='contacts',
+        null=True,
+        blank=True,
+        verbose_name='Владелец',
+    )
     name = models.CharField(max_length=255, verbose_name='Имя')
     email = models.EmailField(blank=True, verbose_name='Email')
     phone = models.CharField(max_length=50, blank=True, verbose_name='Телефон')
@@ -31,6 +40,14 @@ class Contact(models.Model):
 class NetworkMapType(models.Model):
     """Тип карты сети: настраиваемые секторы и концентрические круги."""
 
+    owner = models.ForeignKey(
+        settings.AUTH_USER_MODEL,
+        on_delete=models.CASCADE,
+        related_name='network_map_types',
+        null=True,
+        blank=True,
+        verbose_name='Владелец',
+    )
     name = models.CharField(max_length=255, verbose_name='Название типа')
     sectors = models.JSONField(default=list, verbose_name='Секторы')
     circles = models.JSONField(default=list, verbose_name='Круги')
@@ -54,6 +71,14 @@ class NetworkMapType(models.Model):
 class NetworkMap(models.Model):
     """Карта сети — отдельный контекст для визуализации подмножества контактов."""
 
+    owner = models.ForeignKey(
+        settings.AUTH_USER_MODEL,
+        on_delete=models.CASCADE,
+        related_name='network_maps',
+        null=True,
+        blank=True,
+        verbose_name='Владелец',
+    )
     name = models.CharField(max_length=255, verbose_name='Название')
     description = models.TextField(blank=True, verbose_name='Описание')
     map_type = models.ForeignKey(
@@ -136,6 +161,14 @@ class NetworkMapMembership(models.Model):
 class Relation(models.Model):
     """Связь между двумя контактами."""
 
+    owner = models.ForeignKey(
+        settings.AUTH_USER_MODEL,
+        on_delete=models.CASCADE,
+        related_name='relations',
+        null=True,
+        blank=True,
+        verbose_name='Владелец',
+    )
     source = models.ForeignKey(
         Contact,
         on_delete=models.CASCADE,