Garmin setup

Garmin sync is optional and off by default. It downloads your Garmin activities into the GPS folder, where MTL Explorer imports them.

Create application.yml next to docker-compose.yml with your Garmin login:
```
mtl:
  garmin-sync:
    enabled: true
    user-name: your-garmin-login
    user-password: your-private-password
```
This file contains your password. Allow only your user to read it.
Create or extend compose.override.yml next to it. If it already has an app section, add these lines to it:
```
services:
  app:
    volumes:
      - ./application.yml:/app/config/application.yml:ro
      - ./data/gpx:/app/gpx
```
Keep the existing ./data:/app/mtl-data line in docker-compose.yml.
Apply the changes:
```
docker compose up -d
```
Open Settings → Import & sync → Garmin → Sync now. Check Garmin command output, then wait until Settings → Processing is done.

Some downloads can fail. MTL Explorer retries failed downloads in a different format, but not every error can be fixed this way. See Garmin export for how it works.