Build a `Button` from its attributes; pair with `Button.text` and `Button.onClick`. The typed `Props` front door (`FS.Skia.UI.Controls.Typed`) is the recommended authoring path.

Set whether a `Button` is interactive (`Attr`; `false` greys it out and suppresses click dispatch). Omitted ≡ enabled.

Emit a fixed `'msg` when the `Button` is clicked (`Attr.onClick`); use `onClickWith` when the message depends on the event.

Emit a `'msg` derived from the `ControlEvent` when the `Button` is clicked — the event-aware counterpart to `Button.onClick`.

Set the `Button` label (`Attr` carrying the caption rendered on the command surface).