container, text, date_picker: width-aware sizing pass

`Container::max_width(px)` mirrors the same flag on `Column` / `Row` — the container reports `min( offered, px )` upwards and the draw pass caps `rect.width` to `px`, so a decorated child wrapped in `container().max_width(260)` no longer needs a `column()`-of-one shell just to access the cap. Propagated through `map_msg`, covered by a test, and documented under the `container` section of `docs/widgets.md`.
`Text::no_truncate()` opts out of the default ellipsis behaviour: when `truncate = false` the draw pass paints the full string even if `measure(text) > rect.width`. Useful for very short labels (calendar days "1"–"31", day-of-week stubs "Lu" / "Mi" / "Sá") inside grid slots whose width is dictated by the parent — a couple of pixels of overflow centred in the rect is invisible, while "..." in place of a single-digit number is loud.
`DatePicker::width(px)` is a layout hint: when set, `build()` derives `header_fs`, `dow_fs` and `day_fs` from the slot width so the worst-case label in each row ("September 2026" in the header, "Mié" / "Sáb" in the DOW row, "30" in the day cell) fits at a sensible size; the design defaults stay as upper bounds. Day and DOW cells also flip on `Text::no_truncate()` as a safety net — heuristic font sizing can't perfectly predict glyph widths across families, and overflowing one pixel beats truncating to "...".

src/draw/layout.rs

@@ -138,6 +138,13 @@ pub( crate ) fn layout_and_draw<Msg: Clone>(
 			let saved_alpha = canvas.global_alpha();
 			canvas.set_global_alpha( saved_alpha * c.opacity );
 
+			let rect = if let Some( mw ) = c.max_width
+			{
+				crate::types::Rect { width: rect.width.min( mw ), ..rect }
+			} else {
+				rect
+			};
+
 			// Surface slot takes precedence over flat background; falls
 			// through to `c.background` when the slot is absent (third-
 			// party theme without the named surface — content still

src/widget/container.rs

@@ -83,6 +83,12 @@ pub struct Container<Msg: Clone>
 	/// container's rounded rectangle, after the fill / surface and
 	/// before the child draws. `None` leaves the chrome flat.
 	pub border:     Option<( Color, f32 )>,
+	/// Optional hard cap on the container's outer width. When the parent
+	/// offers more, the container reports its preferred width as
+	/// `min( offered, max_width )` so it does not stretch to fill.
+	/// Mirrors the same flag on [`Column`](crate::layout::column::Column)
+	/// and [`Row`](crate::layout::row::Row).
+	pub max_width:  Option<f32>,
 }
 
 impl<Msg: Clone> Container<Msg>
@@ -101,6 +107,7 @@ impl<Msg: Clone> Container<Msg>
 			pad_left:   0.0,
 			opacity:    1.0,
 			border:     None,
+			max_width:  None,
 		}
 	}
 
@@ -237,12 +244,22 @@ impl<Msg: Clone> Container<Msg>
 		self
 	}
 
+	/// Cap the container's outer width in logical px. When the parent
+	/// offers a wider rect, the container reports its preferred width as
+	/// `min( offered, w )` so it does not stretch to fill.
+	pub fn max_width( mut self, w: f32 ) -> Self
+	{
+		self.max_width = Some( w );
+		self
+	}
+
 	/// Return the preferred `(width, height)` accounting for padding.
 	pub fn preferred_size( &self, max_width: f32, canvas: &Canvas ) -> ( f32, f32 )
 	{
+		let avail = self.max_width.map( |m| max_width.min( m ) ).unwrap_or( max_width );
 		let pad_x = self.pad_left + self.pad_right;
 		let pad_y = self.pad_top  + self.pad_bottom;
-		let inner_w = ( max_width - pad_x ).max( 0.0 );
+		let inner_w = ( avail - pad_x ).max( 0.0 );
 		let ( cw, ch ) = self.child.preferred_size( inner_w, canvas );
 		( cw + pad_x, ch + pad_y )
 	}
@@ -264,6 +281,7 @@ impl<Msg: Clone> Container<Msg>
 			pad_left:   self.pad_left,
 			opacity:    self.opacity,
 			border:     self.border,
+			max_width:  self.max_width,
 		}
 	}
 }
@@ -378,5 +396,15 @@ mod tests
 		let c = container::<()>( spacer() ).surface( "surface-card" );
 		assert_eq!( c.surface.as_deref(), Some( "surface-card" ) );
 	}
+
+	#[ test ]
+	fn max_width_caps_preferred_width()
+	{
+		use crate::render::Canvas;
+		let canvas = Canvas::new( 800, 600 );
+		let c = container::<()>( spacer() ).max_width( 200.0 );
+		let ( w, _ ) = c.preferred_size( 800.0, &canvas );
+		assert!( w <= 200.0 );
+	}
 }
 

src/widget/date_picker.rs

@@ -213,6 +213,7 @@ pub struct DatePicker<Msg: Clone>
 	pub on_change:    Option<Arc<dyn Fn( Date ) -> Msg>>,
 	pub on_navigate:  Option<Arc<dyn Fn( i32, u8 ) -> Msg>>,
 	pub locale:       Locale,
+	pub width:        Option<f32>,
 }
 
 impl<Msg: Clone + 'static> DatePicker<Msg>
@@ -231,6 +232,7 @@ impl<Msg: Clone + 'static> DatePicker<Msg>
 			on_change:   None,
 			on_navigate: None,
 			locale:      Locale::default(),
+			width:       None,
 		}
 	}
 
@@ -274,6 +276,17 @@ impl<Msg: Clone + 'static> DatePicker<Msg>
 		self
 	}
 
+	/// Outer width the picker will be laid out at. Used to shrink the
+	/// header / day-of-week / day-cell font sizes so the widest labels
+	/// ("30", "September 2026", "Mié") still fit without ellipsis. When
+	/// unset, the picker uses the design defaults and may truncate
+	/// inside very narrow rects.
+	pub fn width( mut self, w: f32 ) -> Self
+	{
+		self.width = Some( w );
+		self
+	}
+
 	/// Build the `Element` tree representing this date picker.
 	pub fn build( self ) -> Element<Msg>
 	{
@@ -290,6 +303,18 @@ impl<Msg: Clone + 'static> DatePicker<Msg>
 		let on_nav   = self.on_navigate.clone();
 		let first    = self.locale.first_dow;
 
+		let ( header_fs, dow_fs, day_fs ) = if let Some( w ) = self.width
+		{
+			let inner_w = ( w - 2.0 * theme::PADDING ).max( 8.0 );
+			let slot_w  = ( ( inner_w - 6.0 * theme::SPACING ) / 7.0 ).max( 4.0 );
+			let day     = ( ( slot_w - 8.0 ) / 1.6 ).clamp( 8.0, theme::DAY_FS );
+			let dow     = ( slot_w / 2.0 ).clamp( 8.0, theme::DOW_FS );
+			let head    = ( ( inner_w - 52.0 ) / ( 14.0 * 0.7 ) ).clamp( 10.0, theme::HEADER_FS );
+			( head, dow, day )
+		} else {
+			( theme::HEADER_FS, theme::DOW_FS, theme::DAY_FS )
+		};
+
 		// Header chevrons load from the active theme as SVG icons
 		// (`icons/catalogue/filled/multimedia/{previous,next}.svg`),
 		// tinted to the primary text colour so they read against
@@ -333,11 +358,11 @@ impl<Msg: Clone + 'static> DatePicker<Msg>
 		// `Stack` (the only layout that lets independent children
 		// sit at left / centre / right of the same rect) wrapped in a
 		// container that fixes the row height.
-		let header_height = ( CHEVRON_PX as f32 + 16.0 ).max( theme::HEADER_FS + 16.0 );
+		let header_height = ( CHEVRON_PX as f32 + 16.0 ).max( header_fs + 16.0 );
 		let header_inner: Element<Msg> = stack::<Msg>()
 			.push_aligned( prev, HAlign::Start, VAlign::Center )
 			.push_aligned(
-				text( title ).size( theme::HEADER_FS ).color( theme::text() ),
+				text( title ).size( header_fs ).color( theme::text() ),
 				HAlign::Center, VAlign::Center,
 			)
 			.push_aligned( next, HAlign::End, VAlign::Center )
@@ -360,9 +385,10 @@ impl<Msg: Clone + 'static> DatePicker<Msg>
 			let dow = ( ( slot + first ) % 7 ) as u8;
 			let cell: Element<Msg> = container::<Msg>(
 				text( dow_short( dow ) )
-					.size( theme::DOW_FS )
+					.size( dow_fs )
 					.color( theme::text_muted() )
-					.align_center(),
+					.align_center()
+					.no_truncate(),
 			)
 			.padding_h( 0.0 )
 			.padding_v( 4.0 )
@@ -404,9 +430,10 @@ impl<Msg: Clone + 'static> DatePicker<Msg>
 
 				let mut card = container::<Msg>(
 					text( format!( "{}", day ) )
-						.size( theme::DAY_FS )
+						.size( day_fs )
 						.color( label_color )
-						.align_center(),
+						.align_center()
+						.no_truncate(),
 				)
 				.padding_h( 4.0 )
 				.padding_v( 8.0 )

src/widget/text.rs

@@ -20,11 +20,17 @@ pub enum TextAlign
 
 pub struct Text
 {
-	pub content: String,
-	pub size:    f32,
-	pub color:   Color,
-	pub align:   TextAlign,
-	pub wrap:    bool,
+	pub content:  String,
+	pub size:     f32,
+	pub color:    Color,
+	pub align:    TextAlign,
+	pub wrap:     bool,
+	/// When `true` (default), overflowing single-line text is truncated
+	/// with an ellipsis. When `false`, the full string is painted even
+	/// if it extends past the layout rect — useful for very short
+	/// labels (calendar day numbers, day-of-week stubs) where a couple
+	/// of pixels of overflow is invisible but "..." is noisy.
+	pub truncate: bool,
 	/// Optional `(family, weight, style)` override resolved through
 	/// the active theme's font registry on every draw. `None` keeps
 	/// the canvas default font (Sora Regular in `ltk-theme-default`).
@@ -37,15 +43,22 @@ impl Text
 	{
 		Self
 		{
-			content: content.into(),
-			size:    16.0,
-			color:   Color::WHITE,
-			align:   TextAlign::Left,
-			wrap:    false,
-			font:    None,
+			content:  content.into(),
+			size:     16.0,
+			color:    Color::WHITE,
+			align:    TextAlign::Left,
+			wrap:     false,
+			truncate: true,
+			font:     None,
 		}
 	}
 
+	pub fn no_truncate( mut self ) -> Self
+	{
+		self.truncate = false;
+		self
+	}
+
 	/// Set a `(family, weight, style)` override for this text node.
 	/// The triple is resolved through [`Canvas::font_for`] at draw
 	/// time, so missing weights fall through the registry's nearest-
@@ -187,7 +200,7 @@ impl Text
 
 		let text_w = self.measure( &self.content, canvas, font.as_ref() );
 
-		let display = if text_w > rect.width && rect.width > 0.0
+		let display = if self.truncate && text_w > rect.width && rect.width > 0.0
 		{
 			let ellipsis = "...";
 			let ell_w = self.measure( ellipsis, canvas, font.as_ref() );