curl -X PUT https://api.img-src.io/api/v1/settings/presets/preset_abc123 \
  -H "Authorization: Bearer imgsrc_YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "description": "Updated thumbnail preset",
    "params": {
      "w": 250,
      "h": 250,
      "fit": "cover",
      "format": "webp",
      "q": 85
    }
  }'

{
  "id": "preset_abc123",
  "name": "thumbnail",
  "description": "Updated thumbnail preset",
  "params": {
    "w": 250,
    "h": 250,
    "fit": "cover",
    "format": "webp",
    "q": 85
  },
  "created_at": 1704067200,
  "updated_at": 1704153600
}