Improve text selection accuracy by using the real font family

Enhanced the text layer creation process by using the real font family
instead of the fallback font name. This change ensures that text selection
is more accurate.

src/core/evaluator.js

@@ -2526,7 +2526,7 @@ class PartialEvaluator {
       if (!seenStyles.has(loadedName)) {
         seenStyles.add(loadedName);
         textContent.styles[loadedName] = {
-          fontFamily: font.fallbackName,
+          fontFamily: loadedName,
           ascent: font.ascent,
           descent: font.descent,
           vertical: font.vertical,

src/display/font_loader.js

@@ -66,10 +66,12 @@ class FontLoader {
   }
 
   clear() {
-    for (const nativeFontFace of this.nativeFontFaces) {
-      this._document.fonts.delete(nativeFontFace);
+    const fontFacesToRemove = new Set(this.nativeFontFaces);
+    for (const font of fontFacesToRemove) {
+      if (!this._document.fonts.has(font)) {
+        this.nativeFontFaces.delete(font);
+      }
     }
-    this.nativeFontFaces.clear();
     this.#systemFonts.clear();
 
     if (this.styleElement) {