refactor: split every monolithic module into focused submodules

Each source file that had grown beyond a single concern is replaced by an identically-named directory containing focused submodules. `src/event_loop/mod.rs` (878 lines) becomes a directory with clipboard, context_menu, cursor_shape, drag, focus, handlers, invalidation, overlays_reconcile, repeat, run, surface, text_editing, and tooltip. Every widget, input handler, and theme component follows the same split. Public interfaces are unchanged — only the internal file layout moves.
image bumped from 0.25.2 to 0.25.9.

src/widget/list_item/mod.rs

@@ -0,0 +1,223 @@
+// SPDX-License-Identifier: LGPL-2.1-only
+// Copyright (C) 2026 Liberux Labs, S. L. <info@liberux.net>
+
+use crate::types::{ Rect, WidgetId };
+use crate::render::Canvas;
+use super::Element;
+
+mod theme;
+
+#[cfg(test)]
+mod tests;
+
+/// A row inside a list with a primary label and optional subtitle / trailing
+/// text.
+///
+/// Use to build settings menus, navigation lists, contact rows or any other
+/// vertically-stacked tappable content. The widget paints its own hover and
+/// pressed surfaces and a rounded focus ring; wrap a column of `ListItem`s
+/// inside a [`scroll`](crate::scroll) for scrollable lists.
+///
+/// ```rust,no_run
+/// # use ltk::{ column, list_item, scroll, Element };
+/// # #[ derive( Clone ) ] enum Msg { OpenWifi, OpenBluetooth, OpenDisplay }
+/// # fn _ex() -> Element<Msg> {
+/// // In view():
+/// scroll(
+///     column()
+///         .push( list_item( "Wi-Fi" ).trailing( "Eduroam" ).on_press( Msg::OpenWifi ) )
+///         .push( list_item( "Bluetooth" ).subtitle( "AirPods Pro" ).on_press( Msg::OpenBluetooth ) )
+///         .push( list_item( "Display" ).trailing( "Light" ).on_press( Msg::OpenDisplay ) ),
+/// )
+/// .into()
+/// # }
+/// ```
+pub struct ListItem<Msg: Clone>
+{
+	/// Primary label (always visible, top-aligned when a subtitle is
+	/// present).
+	pub label:    String,
+	/// Optional secondary line drawn below the label in muted colour.
+	/// Doubles the row height when set.
+	pub subtitle: Option<String>,
+	/// Optional right-aligned text (current setting, badge count, "›"
+	/// disclosure). Drawn in muted colour.
+	pub trailing: Option<String>,
+	/// Message emitted on tap. `None` keeps the item visible but inert.
+	pub on_press: Option<Msg>,
+	/// Optional stable identifier for focus management.
+	pub id:       Option<WidgetId>,
+	/// `true` paints the row with the dark selected surface and white
+	/// text, regardless of hover / press state. Use to indicate the
+	/// active item in a list of choices (combo dropdown, segmented
+	/// picker, settings group with a single active value).
+	pub selected: bool,
+}
+
+impl<Msg: Clone> ListItem<Msg>
+{
+	/// Create a list item with the given primary label, no subtitle, no
+	/// trailing text and no callback.
+	pub fn new( label: impl Into<String> ) -> Self
+	{
+		Self
+		{
+			label:    label.into(),
+			subtitle: None,
+			trailing: None,
+			on_press: None,
+			id:       None,
+			selected: false,
+		}
+	}
+
+	/// Mark this row as the currently-selected option in its list.
+	/// Selected rows paint with a dark surface and white text and
+	/// override hover / press visuals.
+	pub fn selected( mut self, yes: bool ) -> Self
+	{
+		self.selected = yes;
+		self
+	}
+
+	/// Add a secondary line below the label. Doubles the row height to
+	/// fit both lines comfortably.
+	pub fn subtitle( mut self, s: impl Into<String> ) -> Self
+	{
+		self.subtitle = Some( s.into() );
+		self
+	}
+
+	/// Add right-aligned text (settings value, badge, disclosure arrow).
+	pub fn trailing( mut self, s: impl Into<String> ) -> Self
+	{
+		self.trailing = Some( s.into() );
+		self
+	}
+
+	/// Set the message emitted when the row is tapped.
+	pub fn on_press( mut self, msg: Msg ) -> Self
+	{
+		self.on_press = Some( msg );
+		self
+	}
+
+	/// Assign a stable identifier for focus management.
+	pub fn id( mut self, id: WidgetId ) -> Self
+	{
+		self.id = Some( id );
+		self
+	}
+
+	pub fn preferred_size( &self, max_width: f32, _canvas: &Canvas ) -> (f32, f32)
+	{
+		let h = if self.subtitle.is_some() { theme::HEIGHT_SUB } else { theme::HEIGHT };
+		( max_width, h )
+	}
+
+	/// Focus stroke is centered on `rect`, so half the stroke width plus ~1 px
+	/// of antialiasing bleed sits outside.
+	pub fn paint_bounds( &self, rect: Rect ) -> Rect
+	{
+		rect.expand( theme::FOCUS_W * 0.5 + 1.0 )
+	}
+
+	pub fn draw( &self, canvas: &mut Canvas, rect: Rect, focused: bool, hovered: bool, pressed: bool )
+	{
+		// Selected wins over hover and press: a chosen item stays
+		// chosen even when the pointer is over it.
+		let ( label_color, subtitle_color, trailing_color ) = if self.selected
+		{
+			canvas.fill_rect( rect, theme::selected_bg(), theme::RADIUS );
+			// Selected row is filled with `text_primary` colour;
+			// label / subtitle / trailing read as the inverse via
+			// `bg` so they stay legible.
+			let inverse = crate::theme::palette().bg;
+			( inverse, inverse, inverse )
+		}
+		else
+		{
+			if pressed
+			{
+				canvas.fill_rect( rect, theme::press_bg(), theme::RADIUS );
+			}
+			else if hovered
+			{
+				canvas.fill_rect( rect, theme::hover_bg(), theme::RADIUS );
+			}
+			( theme::label_color(), theme::subtitle_color(), theme::trailing_color() )
+		};
+
+		if focused
+		{
+			canvas.stroke_rect( rect, theme::focus_color(), theme::FOCUS_W, theme::RADIUS );
+		}
+
+		let has_sub  = self.subtitle.is_some();
+		let label_y  = if has_sub
+		{
+			rect.y + rect.height * 0.35 + theme::LABEL_SIZE * 0.3
+		} else {
+			rect.y + ( rect.height + theme::LABEL_SIZE ) / 2.0 - 2.0
+		};
+
+		canvas.draw_text( &self.label, rect.x + theme::PAD_H, label_y, theme::LABEL_SIZE, label_color );
+
+		if let Some( ref sub ) = self.subtitle
+		{
+			let sub_y = rect.y + rect.height * 0.62 + theme::SUBTITLE_SIZE * 0.3;
+			canvas.draw_text( sub, rect.x + theme::PAD_H, sub_y, theme::SUBTITLE_SIZE, subtitle_color );
+		}
+
+		if let Some( ref trail ) = self.trailing
+		{
+			let tw = canvas.measure_text( trail, theme::TRAILING_SIZE );
+			let tx = rect.x + rect.width - theme::PAD_H - tw;
+			let ty = rect.y + ( rect.height + theme::TRAILING_SIZE ) / 2.0 - 2.0;
+			canvas.draw_text( trail, tx, ty, theme::TRAILING_SIZE, trailing_color );
+		}
+	}
+
+	pub( crate ) fn map_msg<U>( self, f: &super::MapFn<Msg, U> ) -> ListItem<U>
+	where
+		U: Clone + 'static,
+		Msg: 'static,
+	{
+		ListItem
+		{
+			label:    self.label,
+			subtitle: self.subtitle,
+			trailing: self.trailing,
+			on_press: self.on_press.map( |m| ( *f )( m ) ),
+			id:       self.id,
+			selected: self.selected,
+		}
+	}
+}
+
+/// Create a [`ListItem`] with the given primary label.
+///
+/// Add detail and behaviour through the chained builders:
+///
+/// ```rust,no_run
+/// # use ltk::{ list_item, ListItem };
+/// # #[ derive( Clone ) ] enum Msg { OpenDisplay }
+/// # fn _ex() -> ListItem<Msg> {
+/// list_item( "Display" )
+///     .subtitle( "Resolution, brightness, night mode" )
+///     .trailing( "›" )
+///     .on_press( Msg::OpenDisplay )
+/// # }
+/// ```
+pub fn list_item<Msg: Clone>( label: impl Into<String> ) -> ListItem<Msg>
+{
+	ListItem::new( label )
+}
+
+impl<Msg: Clone + 'static> From<ListItem<Msg>> for Element<Msg>
+{
+	fn from( l: ListItem<Msg> ) -> Self
+	{
+		Element::ListItem( l )
+	}
+}

src/widget/list_item/tests.rs

@@ -0,0 +1,14 @@
+// SPDX-License-Identifier: LGPL-2.1-only
+// Copyright (C) 2026 Liberux Labs, S. L. <info@liberux.net>
+
+use super::*;
+
+#[test]
+fn list_item_default()
+{
+	let l = list_item::<()>( "Test" );
+	assert_eq!( l.label, "Test" );
+	assert!( l.subtitle.is_none() );
+	assert!( l.trailing.is_none() );
+	assert!( l.on_press.is_none() );
+}

src/widget/list_item/theme.rs

@@ -0,0 +1,33 @@
+// SPDX-License-Identifier: LGPL-2.1-only
+// Copyright (C) 2026 Liberux Labs, S. L. <info@liberux.net>
+
+use crate::types::Color;
+pub fn label_color()    -> Color { crate::theme::palette().text_primary }
+pub fn subtitle_color() -> Color { crate::theme::palette().text_secondary }
+pub fn trailing_color() -> Color { crate::theme::palette().text_secondary }
+/// Alpha-only overlay tuned for the active mode (white on dark, navy on light).
+pub fn hover_bg() -> Color
+{
+	let p = crate::theme::palette();
+	Color { r: p.text_primary.r, g: p.text_primary.g, b: p.text_primary.b, a: 0.06 }
+}
+pub fn press_bg() -> Color
+{
+	let p = crate::theme::palette();
+	Color { r: p.text_primary.r, g: p.text_primary.g, b: p.text_primary.b, a: 0.12 }
+}
+/// Solid dark surface for the [`ListItem::selected`](super::ListItem::selected) state.
+/// `palette.text_primary` happens to be the right colour for both
+/// modes (navy on light, white on dark) so the white-on-dark contrast
+/// pattern flips into a navy-on-white contrast in dark mode without
+/// needing a separate slot.
+pub fn selected_bg() -> Color { crate::theme::palette().text_primary }
+pub fn focus_color() -> Color { crate::theme::palette().accent }
+pub const LABEL_SIZE:    f32 = 16.0;
+pub const SUBTITLE_SIZE: f32 = 13.0;
+pub const TRAILING_SIZE: f32 = 14.0;
+pub const HEIGHT:        f32 = 56.0;
+pub const HEIGHT_SUB:    f32 = 68.0;
+pub const PAD_H:         f32 = 16.0;
+pub const RADIUS:        f32 = 12.0;
+pub const FOCUS_W:       f32 = 2.0;