feat: add JWT auth foundation - /api/v1/ with admin login, refresh, me, health endpoints

- Add djangorestframework-simplejwt==5.3.1 to requirements-docker.txt
- Configure REST_FRAMEWORK with JWTAuthentication and SIMPLE_JWT settings
- Create admin_api Django app with AdminLoginView, MeView, HealthView
- Wire /api/v1/ routes without touching existing /api/ mobile endpoints
- Resolve pre-existing events migration conflict (0010_merge)
- Superuser admin created for initial authentication

events/migrations/0010_merge_20260324_1443.py

@@ -0,0 +1,14 @@
+# Generated by Django 4.2.21 on 2026-03-24 14:43
+
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('events', '0007_add_is_featured_is_top_event'),
+        ('events', '0009_alter_event_id_alter_eventimages_id'),
+    ]
+
+    operations = [
+    ]