Fix #26402: Formatting lost when special character is copied and pasted

Copying and pasting a musical symbol with a modified size in a system
text object caused the size to reset. This happened because the cursor
used during insertion was from the paste location rather than the copied
element. Additionally, the format was not properly stored in the edit
text object (ed), so when TextBase::insertSym() was called, it
lacked the correct formatting.
I fixed this by ensuring the correct cursor was used for insertion
and explicitly setting the format in the edit text object before
passing it to TextBase::insertSym() during TextBase::paste(),
preserving the symbol’s modified size.

Author: mafaldarpdias

src/engraving/dom/textedit.cpp

@@ -271,7 +271,7 @@ void TextBase::insertSym(EditData& ed, SymId id)
     deleteSelectedText(ed);
     String s = score()->engravingFont()->toString(id);
     cursor->format()->setFontFamily(u"ScoreText");
-    score()->undo(new InsertText(m_cursor, s), &ed);
+    score()->undo(new InsertText(cursor, s), &ed);
 }
 
 //---------------------------------------------------------
@@ -940,6 +940,7 @@ void TextBase::paste(EditData& ed, const String& txt)
                     sym.clear();
                 } else if (token == "/sym") {
                     symState = false;
+                    static_cast<TextEditData*>(ed.getData(this).get())->cursor()->setFormat(format);
                     insertSym(ed, SymNames::symIdByName(sym));
                 } else {
                     prepareFormat(token, format);