Fix regroup rhythms not maintaining selection

Fixes: #24955

cmdResetNoteAndRestGroupings already saved the current selection before
actually regrouping rhythms. This commit updates the method to set the
selection to the values saved in the case that the user had selected a
range before calling regroup rhythms.

Also adds test to verify that selection is maintained when regrouping
rhythms.

src/engraving/dom/cmd.cpp

@@ -2803,7 +2803,12 @@ void Score::cmdResetNoteAndRestGroupings()
 
     if (noSelection) {
         deselectAll();
+        return;
     }
+
+    // Reset selection to original selection
+    selection().setRangeTicks(sTick, eTick, sStaff, eStaff);
+    selection().updateSelectedElements();
 }
 
 static void resetBeamOffSet(void*, EngravingItem* e)

src/engraving/tests/rhythmicgrouping_tests.cpp

@@ -103,3 +103,45 @@ TEST_F(Engraving_RhythmicGroupingTests, groupShortenNotes)
 {
     group("groupShortenNotes.mscx", "groupShortenNotes-ref.mscx");  // test for regrouping rhythms when notes should be shortened
 }
+
+TEST_F(Engraving_RhythmicGroupingTests, groupMaintainSelection)
+{
+    MasterScore* score = ScoreRW::readScore(RHYTHMICGRP_DATA_DIR + String::fromUtf8("groupSubbeats.mscx"));
+    ASSERT_TRUE(score);
+
+    score->cmdSelectAll();
+
+    const Selection& selection = score->selection();
+    Fraction sTick = selection.tickStart();
+    Fraction eTick = selection.tickEnd();
+    staff_idx_t sStaff = selection.staffStart();
+    staff_idx_t eStaff = selection.staffEnd();
+
+    score->cmdResetNoteAndRestGroupings();
+
+    EXPECT_EQ(sTick, score->selection().tickStart());
+    EXPECT_EQ(eTick, score->selection().tickEnd());
+    EXPECT_EQ(sStaff, score->selection().staffStart());
+    EXPECT_EQ(eStaff, score->selection().staffEnd());
+}
+
+TEST_F(Engraving_RhythmicGroupingTests, groupMaintainSelectionMultipleStaves)
+{
+    MasterScore* score = ScoreRW::readScore(RHYTHMICGRP_DATA_DIR + String::fromUtf8("group8ths4-4.mscx"));
+    ASSERT_TRUE(score);
+
+    score->cmdSelectAll();
+
+    const Selection& selection = score->selection();
+    Fraction sTick = selection.tickStart();
+    Fraction eTick = selection.tickEnd();
+    staff_idx_t sStaff = selection.staffStart();
+    staff_idx_t eStaff = selection.staffEnd();
+
+    score->cmdResetNoteAndRestGroupings();
+
+    EXPECT_EQ(sTick, score->selection().tickStart());
+    EXPECT_EQ(eTick, score->selection().tickEnd());
+    EXPECT_EQ(sStaff, score->selection().staffStart());
+    EXPECT_EQ(eStaff, score->selection().staffEnd());
+}