feat: add Django web app, CloudKit sync, dashboard, and game_datetime_utc export

Adds the full Django application layer on top of sportstime_parser:
- core: Sport, Team, Stadium, Game models with aliases and league structure
- scraper: orchestration engine, adapter, job management, Celery tasks
- cloudkit: CloudKit sync client, sync state tracking, sync jobs
- dashboard: staff dashboard for monitoring scrapers, sync, review queue
- notifications: email reports for scrape/sync results
- Docker setup for deployment (Dockerfile, docker-compose, entrypoint)

Game exports now use game_datetime_utc (ISO 8601 UTC) instead of
venue-local date+time strings, matching the canonical format used
by the iOS app.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

sportstime/celery.py

@@ -0,0 +1,22 @@
+import os
+
+from celery import Celery
+
+# Set the default Django settings module for the 'celery' program.
+os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'sportstime.settings')
+
+app = Celery('sportstime')
+
+# Using a string here means the worker doesn't have to serialize
+# the configuration object to child processes.
+# - namespace='CELERY' means all celery-related configuration keys
+#   should have a `CELERY_` prefix.
+app.config_from_object('django.conf:settings', namespace='CELERY')
+
+# Load task modules from all registered Django apps.
+app.autodiscover_tasks()
+
+
+@app.task(bind=True, ignore_result=True)
+def debug_task(self):
+    print(f'Request: {self.request!r}')