feat: improve MQTT reconnection handling + document arrival notifier

- Add keepalive (60s), reconnectPeriod (5s), connectTimeout (30s)
- Add offline/close event handlers with proper logging
- Document Tesla Arrival Notifier setup in README
- Document systemd service installation

README.md

@@ -159,6 +159,78 @@ Messages are prefixed with the topic for context:
 ### Webhook returns 401
 - Token mismatch — check `hooks.token` in Clawdbot config matches `CLAWDBOT_TOKEN`
 
+---
+
+## Tesla Arrival Notifier
+
+A specialized component that monitors TeslaMate MQTT for car state changes and notifies Clawdbot when you arrive somewhere.
+
+### How It Works
+
+1. Subscribes to TeslaMate MQTT topics (`teslamate/cars/<id>/state`, `geofence`, `latitude`, `longitude`)
+2. Detects when car state transitions from `driving` → any stationary state (`online`, `parked`, `charging`, `suspended`, `asleep`, `offline`)
+3. Sends arrival notification to Clawdbot with geofence name (or reverse-geocoded address)
+4. Clawdbot checks `location-reminders.json` for location-specific reminders
+
+### Installation
+
+```bash
+# Install to /opt
+sudo mkdir -p /opt/mqtt-clawdbot-bridge
+sudo cp arrival-notifier.js package*.json /opt/mqtt-clawdbot-bridge/
+cd /opt/mqtt-clawdbot-bridge && npm install
+
+# Install systemd service
+sudo cp arrival-notifier.service /etc/systemd/system/
+sudo systemctl daemon-reload
+sudo systemctl enable arrival-notifier
+sudo systemctl start arrival-notifier
+```
+
+### Configuration
+
+Environment variables (configured in the systemd service file):
+
+| Variable | Default | Description |
+|----------|---------|-------------|
+| `MQTT_URL` | `mqtts://mqtt.teslamate.olex.me:8883` | TeslaMate MQTT broker |
+| `MQTT_USERNAME` | `olex` | MQTT username |
+| `MQTT_PASSWORD` | — | MQTT password (**required**) |
+| `CLAWDBOT_URL` | `http://127.0.0.1:18789` | Clawdbot gateway URL |
+| `CLAWDBOT_TOKEN` | — | Webhook token (**required**) |
+| `CAR_ID` | `14` | TeslaMate car ID |
+| `LOG_LEVEL` | `info` | `debug` for verbose output |
+
+### Managing the Service
+
+```bash
+# Check status
+sudo systemctl status arrival-notifier
+
+# View logs
+journalctl -u arrival-notifier -f
+
+# Restart after config changes
+sudo systemctl restart arrival-notifier
+```
+
+### Location Reminders
+
+Create `~/clawd/location-reminders.json`:
+
+```json
+{
+  "Zuhause (Geißberg 31)": [
+    "Reminder: Check the mailbox!"
+  ],
+  "Arbeit (GUDE)": [
+    "Remember to submit timesheet on Fridays"
+  ]
+}
+```
+
+Geofence names must match exactly as shown in TeslaMate.
+
 ## License
 
 MIT