migrate fonts to scoped resource ownership

- replace FontManager with per-ResourceScope FontService instances
  - publish font factories into explicit or default resource scopes
  - import default resources into UI scene scopes unless explicitly disabled
  - keep related font faces strongly owned without hot-path weak_ptr locking
  - add cached glyph advance queries without creating texture pages
  - fix font picker preview ownership, cleanup, and rapid switching
  - selectively evict TextLayout cache entries when referenced fonts unload
  - document FontService, ResourceCatalog, and cache invalidation semantics
  - migrate examples, tools, benchmarks, and tests to the scoped font API
  - expand coverage for font ownership, texture release, and layout caching

src/examples/fonts/fonts.cpp

@@ -25,23 +25,24 @@ EE_MAIN_FUNC int main( int, char*[] ) {
 				"cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non "
 				"proident, sunt in culpa qui officia deserunt mollit anim id est laborum." );
 
-	FontTrueType* fontTest = FontTrueType::New( "DejaVuSansMono" );
+	FontTrueType* fontTest = FontTrueType::New( "DejaVuSansMono" ).get();
 	fontTest->loadFromFile( "assets/fonts/DejaVuSansMono.ttf" );
 
-	FontTrueType* fontTest2 = FontTrueType::New( "NotoSans-Regular" );
+	FontTrueType* fontTest2 = FontTrueType::New( "NotoSans-Regular" ).get();
 	fontTest2->loadFromFile( "assets/fonts/NotoSans-Regular.ttf" );
 
-	FontTrueType* fontEmoji = FontTrueType::New( "NotoEmoji-Regular" );
+	FontTrueType* fontEmoji = FontTrueType::New( "NotoEmoji-Regular" ).get();
 	fontEmoji->loadFromFile( "assets/fonts/NotoEmoji-Regular.ttf" );
 
-	FontTrueType* fontEmojiColor = FontTrueType::New( "NotoColorEmoji" );
+	FontTrueType* fontEmojiColor = FontTrueType::New( "NotoColorEmoji" ).get();
 	fontEmojiColor->loadFromFile( "assets/fonts/NotoColorEmoji.ttf" );
 
-	FontBMFont* fontBMFont = FontBMFont::New( "bmfont" );
+	FontBMFont* fontBMFont = FontBMFont::New( "bmfont" ).get();
 	fontBMFont->loadFromFile( "assets/fonts/bmfont.fnt" );
 
-	FontSprite* fontSprite = FontSprite::New(
-		"alagard" ); // Alagard - Hewett Tsoi ( https://www.dafont.com/alagard.font )
+	FontSprite* fontSprite =
+		FontSprite::New( "alagard" )
+			.get(); // Alagard - Hewett Tsoi ( https://www.dafont.com/alagard.font )
 	fontSprite->loadFromFile( "assets/fonts/custom_alagard.png", Color::Fuchsia, 32, -4 );
 
 	Text text;

src/examples/richtext/richtext.cpp

@@ -9,7 +9,7 @@ EE_MAIN_FUNC int main( int argc, char* argv[] ) {
 	FileSystem::changeWorkingDirectory( Sys::getProcessPath() );
 
 	FontTrueType* font =
-		FontTrueType::New( "NotoSans-Regular", "assets/fonts/NotoSans-Regular.ttf" );
+		FontTrueType::New( "NotoSans-Regular", "assets/fonts/NotoSans-Regular.ttf" ).get();
 
 	if ( !font || !font->loaded() )
 		return EXIT_FAILURE;

src/examples/ui_font_picker/ui_font_picker.cpp

@@ -10,10 +10,15 @@ EE_MAIN_FUNC int main( int, char** ) {
 		return EXIT_FAILURE;
 
 	app.getUI()->setThreadPool( threadPool );
+	ResourceScope& resourceScope = *app.getUI()->getResourceScope();
+	FontTrueTypePtr remixIconFont =
+		FontTrueType::New( "icon", "assets/fonts/remixicon.ttf", resourceScope );
+	FontTrueTypePtr noniconsFont =
+		FontTrueType::New( "nonicons", "assets/fonts/nonicons.ttf", resourceScope );
+	FontTrueTypePtr codIconFont =
+		FontTrueType::New( "codicon", "assets/fonts/codicon.ttf", resourceScope );
 	app.getUI()->getUIIconThemeManager()->setCurrentTheme(
-		IconManager::init( "icons", FontTrueType::New( "icon", "assets/fonts/remixicon.ttf" ),
-						   FontTrueType::New( "nonicons", "assets/fonts/nonicons.ttf" ),
-						   FontTrueType::New( "codicon", "assets/fonts/codicon.ttf" ) ) );
+		IconManager::init( "icons", remixIconFont.get(), noniconsFont.get(), codIconFont.get() ) );
 
 	UIFontPickerDialog* dialog = UIFontPickerDialog::New();
 	dialog->setCloseShortcut( KEY_ESCAPE );

src/examples/ui_hello_world/ui_hello_world.cpp

@@ -13,13 +13,12 @@ EE_MAIN_FUNC int main( int, char** ) {
 	// is always correct even if we load the application from other directory than the binary
 	// path.
 	FileSystem::changeWorkingDirectory( Sys::getProcessPath() );
-
-	// Load a font to use as the default font in our UI.
-	FontTrueType* font =
-		FontTrueType::New( "NotoSans-Regular", "assets/fonts/NotoSans-Regular.ttf" );
-
 	// Create a new scene node to add our widgets.
 	UISceneNode* uiSceneNode = UISceneNode::New();
+	// Load a font to use as the default font in our UI.
+	FontTrueType* font = FontTrueType::New( "NotoSans-Regular", "assets/fonts/NotoSans-Regular.ttf",
+											*uiSceneNode->getResourceScope() )
+							 .get();
 
 	// Set the default font used in the scene node (otherwise we won't have any font to create
 	// text views.

src/examples/ui_html/ui_html.cpp

@@ -63,11 +63,15 @@ EE_MAIN_FUNC int main( int argc, char** argv ) {
 	auto ui = app.getUI();
 	ui->setThreadPool( threadPool );
 
-	FontTrueType* remixIconFont = FontTrueType::New( "icon", "assets/fonts/remixicon.ttf" );
-	FontTrueType* noniconsFont = FontTrueType::New( "nonicons", "assets/fonts/nonicons.ttf" );
-	FontTrueType* codIconFont = FontTrueType::New( "codicon", "assets/fonts/codicon.ttf" );
+	ResourceScope& resourceScope = *ui->getResourceScope();
+	FontTrueTypePtr remixIconFont =
+		FontTrueType::New( "icon", "assets/fonts/remixicon.ttf", resourceScope );
+	FontTrueTypePtr noniconsFont =
+		FontTrueType::New( "nonicons", "assets/fonts/nonicons.ttf", resourceScope );
+	FontTrueTypePtr codIconFont =
+		FontTrueType::New( "codicon", "assets/fonts/codicon.ttf", resourceScope );
 	ui->getUIIconThemeManager()->setCurrentTheme(
-		IconManager::init( "icons", remixIconFont, noniconsFont, codIconFont ) );
+		IconManager::init( "icons", remixIconFont.get(), noniconsFont.get(), codIconFont.get() ) );
 
 	ui->setColorSchemePreference(
 		!prefersColorScheme.Get().empty()