feat: RFCP MVP deployed on VPS

Iteration 1:
- Dark theme with 3-way toggle
- Dynamic heatmap gradient (blue→red)
- Radius up to 100km
- Save & Calculate workflow

Iteration 2:
- Terrain overlay toggle
- Batch height operations
- Zoom-dependent heatmap rendering

Infrastructure:
- Backend FastAPI on 8888
- Frontend static build via Caddy
- Systemd services
- Caddy reverse proxy integration

backend/venv/lib/python3.12/site-packages/aiofiles/__init__.py

@@ -0,0 +1,23 @@
+"""Utilities for asyncio-friendly file handling."""
+
+from . import tempfile
+from .threadpool import (
+    open,
+    stderr,
+    stderr_bytes,
+    stdin,
+    stdin_bytes,
+    stdout,
+    stdout_bytes,
+)
+
+__all__ = [
+    "open",
+    "tempfile",
+    "stdin",
+    "stdout",
+    "stderr",
+    "stdin_bytes",
+    "stdout_bytes",
+    "stderr_bytes",
+]