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/.env.example

@@ -2,7 +2,7 @@
 # Get this from: Cloudflare Zero Trust > Networks > Tunnels > Create > Docker
 CLOUDFLARE_TUNNEL_TOKEN=your-tunnel-token-here
 
-# Idle auto-shutdown (minutes)
-# App exits after this many minutes with no active viewers
-# Set to 0 to disable (app runs forever)
-IDLE_TIMEOUT_MINUTES=30
+# Idle auto-pause (seconds)
+# Physics engine pauses after this many seconds with no viewers
+# CPU drops to ~0% when paused, resumes instantly on visit
+IDLE_PAUSE_SECONDS=30

deploy/docker-compose.yml

@@ -4,9 +4,9 @@ services:
       context: ..
       dockerfile: Dockerfile
     container_name: py-dvt-ate-streamlit
-    restart: "no"  # Don't auto-restart - we want it to stay stopped when idle
+    restart: unless-stopped
     environment:
-      - IDLE_TIMEOUT_MINUTES=${IDLE_TIMEOUT_MINUTES:-30}
+      - IDLE_PAUSE_SECONDS=${IDLE_PAUSE_SECONDS:-30}  # Pause physics after 30s idle
     expose:
       - "8080"
     volumes:
@@ -39,26 +39,6 @@ services:
     networks:
       - dvt-ate
 
-  # Optional: Auto-start streamlit when stopped (checks every 30s)
-  # Uncomment if you want fully automatic restart on visit
-  # wakeup:
-  #   image: docker:cli
-  #   container_name: py-dvt-ate-wakeup
-  #   restart: unless-stopped
-  #   entrypoint: /bin/sh
-  #   command:
-  #     - -c
-  #     - |
-  #       while true; do
-  #         sleep 30
-  #         if ! docker inspect -f '{{.State.Running}}' py-dvt-ate-streamlit 2>/dev/null | grep -q true; then
-  #           echo "[$(date)] Starting streamlit..."
-  #           docker start py-dvt-ate-streamlit
-  #         fi
-  #       done
-  #   volumes:
-  #     - /var/run/docker.sock:/var/run/docker.sock:ro
-
 networks:
   dvt-ate:
     driver: bridge

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