Simplify deployment - use physics pause instead of container shutdown

- IDLE_PAUSE_SECONDS replaces IDLE_TIMEOUT_MINUTES
- Container stays running, physics pauses when idle
- No restart mechanism needed
- Remove wakeup service (no longer needed)

deploy/readme.md

@@ -2,37 +2,22 @@
 
 Deploy the DVT Simulation Platform dashboard with Cloudflare Tunnel for public access.
 
-## Idle Auto-Shutdown
+## Idle Auto-Pause
 
-The app automatically shuts down after a period of inactivity to save resources.
+The physics simulation automatically pauses when no one is viewing the dashboard.
 
 **Configuration:**
 ```bash
 # In .env or docker-compose.yml
-IDLE_TIMEOUT_MINUTES=30  # Shutdown after 30 min idle (0 = disabled)
+IDLE_PAUSE_SECONDS=30  # Pause physics after 30s idle
 ```
 
 **Behaviour:**
-- App tracks activity when someone has the dashboard open
-- After `IDLE_TIMEOUT_MINUTES` with no viewers, the container exits
-- nginx will show a 502 error until the container is restarted
-
-**Restart Options:**
-
-1. **Manual restart** (simplest):
-   ```bash
-   docker start py-dvt-ate-streamlit
-   ```
-
-2. **Auto-restart on poll** (uncomment `wakeup` service in docker-compose.yml):
-   - Checks every 30 seconds if streamlit is stopped
-   - Automatically restarts it
-   - Adds ~30 second delay before app is available
-
-3. **Always running** (set `IDLE_TIMEOUT_MINUTES=0`):
-   - App never auto-shuts down
-   - Uses minimal CPU when idle (~0.1%)
-   - Memory stays allocated (~300-400MB)
+- When someone views the dashboard, physics runs normally
+- After `IDLE_PAUSE_SECONDS` with no viewers, physics engine pauses
+- CPU drops to ~0% while paused
+- Physics resumes instantly when someone visits
+- Container stays running (no restart needed)
 
 ## Architecture