Add Reddit monitoring bot — backend, frontend, and Docker config

Python/FastAPI backend with PostgreSQL for collecting Reddit data via
public .json endpoints. React/Vite dashboard for analytics. Docker Compose
setup with API and worker services connecting to shared PostgreSQL.

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

backend/worker/summary_job.py

@@ -0,0 +1,12 @@
+import logging
+
+from backend.config import settings
+
+logger = logging.getLogger(__name__)
+
+
+def generate_summaries():
+    """Stub: AI summary generation. Enable when a provider is configured."""
+    if not settings.ai_summary_enabled:
+        return
+    logger.info("AI summary generation not yet configured")