toggle, widget: scale the pill with an explicit row height, and give elide a half-pixel tolerance

Toggle::height used to adjust only the row: the resolved value was floored at the theme track height and the pill kept its theme size, so a toggle capped below the fluid row height still rendered a full-size pill — on large surfaces, visibly out of scale next to controls that honour their cap. The floor is gone; when the resolved height falls below the theme row height, track and thumb now scale down proportionally (never up — the factor is capped at 1), and preferred_size reports the scaled track width so layout, focus ring and centring stay consistent. A toggle without an explicit height is untouched.
elide compared measure( text ) <= max_w strictly, which breaks when the caller sized itself from the same measurement: a button reports text + 2×pad as its preferred width, the layout grants exactly that, and draw hands elide back rect.width − 2×pad. In f32 the add-then-subtract round-trip can land a few ULP under the original measurement, the strict comparison fails, and the truncation branch then costs the full width of the ellipsis — a sub-pixel deficit turned "Empezar" into "Empez...". The fit check now allows half a pixel of slack, which absorbs any mismatch of this class while leaving genuine overflows to truncate as before.

src/widget/mod.rs

@@ -128,7 +128,10 @@ pub( crate ) fn elide(
 	{
 		return String::new();
 	}
-	if canvas.measure_text( text, size ) <= max_w
+	// Half-pixel slack: a parent that sized itself from this same
+	// measurement can hand back a width a few ULP short after its
+	// padding add-then-subtract round-trip.
+	if canvas.measure_text( text, size ) <= max_w + 0.5
 	{
 		return text.to_string();
 	}

src/widget/toggle/mod.rs

@@ -89,9 +89,10 @@ impl<Msg: Clone> Toggle<Msg>
 
 	/// Override the preferred height (default: the theme row height,
 	/// `theme::HEIGHT` design px). Accepts any [`Length`] so dense
-	/// layouts can tie the row height to the viewport. The resolved
+	/// layouts can tie the row height to the viewport. When the resolved
-	/// value is floored at the track height so the pill never clips;
+	/// value falls below the theme row height, the pill (track and thumb)
-	/// the track keeps its theme size and stays vertically centred.
+	/// scales down proportionally so it never clips; it never grows
+	/// beyond its theme size.
 	pub fn height( mut self, h: impl Into<Length> ) -> Self
 	{
 		self.height = Some( h.into() );
@@ -105,7 +106,13 @@ impl<Msg: Clone> Toggle<Msg>
 	/// label is set. Height is the theme-defined row height.
 	pub fn preferred_size( &self, max_width: f32, canvas: &Canvas ) -> (f32, f32)
 	{
-		let track_w = canvas.geom_px( theme::TRACK_W );
+		let h = match self.height
+		{
+			Some( l ) => canvas.resolve_geom( l ),
+			None      => canvas.geom_px( theme::HEIGHT ),
+		};
+		let scale   = ( h / canvas.geom_px( theme::HEIGHT ) ).min( 1.0 );
+		let track_w = canvas.geom_px( theme::TRACK_W ) * scale;
 		let w = if let Some( ref label ) = self.label
 		{
 			let text_w = canvas.measure_text( label, canvas.font_px( theme::FONT_SIZE ) );
@@ -113,11 +120,6 @@ impl<Msg: Clone> Toggle<Msg>
 		} else {
 			track_w.min( max_width )
 		};
-		let h = match self.height
-		{
-			Some( l ) => canvas.resolve_geom( l ).max( canvas.geom_px( theme::TRACK_H ) ),
-			None      => canvas.geom_px( theme::HEIGHT ),
-		};
 		( w, h )
 	}
 
@@ -133,9 +135,10 @@ impl<Msg: Clone> Toggle<Msg>
 
 	pub fn draw( &self, canvas: &mut Canvas, rect: Rect, focused: bool )
 	{
-		let track_w    = canvas.geom_px( theme::TRACK_W );
+		let scale      = ( rect.height / canvas.geom_px( theme::HEIGHT ) ).min( 1.0 );
-		let track_h    = canvas.geom_px( theme::TRACK_H );
+		let track_w    = canvas.geom_px( theme::TRACK_W ) * scale;
-		let thumb_size = canvas.geom_px( theme::THUMB_SIZE );
+		let track_h    = canvas.geom_px( theme::TRACK_H ) * scale;
+		let thumb_size = canvas.geom_px( theme::THUMB_SIZE ) * scale;
 
 		let track_x = if let Some( ref label ) = self.label
 		{