**IconButton** — icon-only square button for table row actions (edit, preview, delete) and toolbars. Always pass `title` for the tooltip/aria-label.

```jsx
<IconButton title="Edit channel"><EditIcon/></IconButton>
<IconButton title="Preview" variant="solid"><PlayIcon/></IconButton>
<IconButton title="Delete" disabled><TrashIcon/></IconButton>
```

Props: `size` (sm·md), `variant` (ghost·solid), `active`, `disabled`, `title`.
