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/spinner/tests.rs

@@ -0,0 +1,38 @@
+// SPDX-License-Identifier: LGPL-2.1-only
+// Copyright (C) 2026 Liberux Labs, S. L. <info@liberux.net>
+
+use super::*;
+
+#[ test ]
+fn defaults()
+{
+	let s = spinner();
+	assert_eq!( s.phase, 0.0 );
+	assert_eq!( s.size, theme::SIZE );
+	assert_eq!( s.stroke_w, theme::STROKE_W );
+}
+
+#[ test ]
+fn builders_apply()
+{
+	let s = spinner().phase( 0.42 ).size( 64.0 ).stroke_width( 5.0 );
+	assert_eq!( s.phase, 0.42 );
+	assert_eq!( s.size, 64.0 );
+	assert_eq!( s.stroke_w, 5.0 );
+}
+
+#[ test ]
+fn preferred_size_clamps_to_max_width()
+{
+	let s = spinner().size( 100.0 );
+	assert_eq!( s.preferred_size( 40.0 ), ( 40.0, 40.0 ) );
+	assert_eq!( s.preferred_size( 200.0 ), ( 100.0, 100.0 ) );
+}
+
+#[ test ]
+fn preferred_size_is_square()
+{
+	let s = spinner();
+	let ( w, h ) = s.preferred_size( 999.0 );
+	assert_eq!( w, h );
+}