feat(reader): improve Japanese selection UX by disabling furigana selection (#4137)

* feat: add default ruby rt styles with user-select: none

* fix: prevent furigana text from being copied via ruby transformer

* fix: register ruby transformer in FoliateViewer pipeline; use span wrapper for reliable ::before rendering

* refactor(reader): simplify furigana copy exclusion

Drop the ruby transformer and the .rt-text::before pseudo-element
wrapping. Instead, pass ['rt'] to getTextFromRange unconditionally so
furigana is excluded from annotator/translation/copy text extraction,
and let `rt { user-select: none }` handle the native selection cursor.

Avoids DOM rewriting and HTML-entity round-tripping in the data-text
attribute, and keeps <rt> text in the DOM for TTS, in-page find, and
screen readers.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Huang Xin <chrox.huang@gmail.com>
Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

apps/readest-app/src/app/reader/components/annotator/Annotator.tsx

@@ -207,7 +207,7 @@ const Annotator: React.FC<{ bookKey: string }> = ({ bookKey }) => {
 
   const getAnnotationText = useCallback(
     async (range: Range) => {
-      transformCtx['content'] = getTextFromRange(range, primaryLang.startsWith('ja') ? ['rt'] : []);
+      transformCtx['content'] = getTextFromRange(range, ['rt']);
       return await transformContent(transformCtx);
     },
     [primaryLang, transformCtx],