[Bug] Not reading caveman.json

Hi, Im trying to keep it enabled by default yet it wont work, i have to use the opencode command /caveman full to enable the plugin.

```sh
cat ~/.config/opencode/caveman.json                {
  "enabled": true,
  "defaultMode": "full",
  "features": {
    "caveman": true,
    "commit": true,
    "review": true
  }
}
```

Please could you fix this?