SIZEGUIDE

A "Size Guide" trigger button that opens a dialog with a measurement table built from params.headers/params.rows. Entirely self-contained — no navigation/fetch callback needed, since the table data ships inline with the widget entry.

{
  "type": "SIZEGUIDE",
  "params": {
    "button_label": "Size Guide",
    "title": "Size Guide",
    "headers": ["Size", "Chest (cm)", "Waist (cm)"],
    "rows": [
      ["S", "88-92", "72-76"],
      ["M", "96-100", "80-84"],
      ["L", "104-108", "88-92"]
    ]
  }
}

• button_label — the trigger button's text. Falls back to theme.sizeGuideButtonLabel ("Size Guide").
• title — the dialog's header. Falls back to the same theme.sizeGuideButtonLabel.
• headers — column headers.
• rows — one list of cell strings per row.
• Hides itself entirely when headers or rows is empty or missing.