Check spanners when assessing emptiness

Previously, a staff's emptiness was calculated based on its note and annotation content. Since this is evaluated before the system was laid out, the system did not have pointers to its SpannerSegments. This commit adds a way to include whether a staff has any spanners
(particularly pedal markings and hanging slurs) in assessing emptiness, creating more consistent/expected hiding behavior in HideMode::AUTO.

Port of musescore#8430, part 2

Author: iveshenry18

src/engraving/rendering/dev/systemlayout.cpp

@@ -590,6 +590,10 @@ void SystemLayout::hideEmptyStaves(System* system, LayoutContext& ctx, bool isFi
     staff_idx_t staffIdx = 0;
     bool systemIsEmpty = true;
 
+    Fraction stick = system->measures().front()->tick();
+    Fraction etick = system->measures().back()->endTick();
+    auto spanners = ctx.dom().spannerMap().findOverlapping(stick.ticks(), etick.ticks());
+
     for (const Staff* staff : ctx.dom().staves()) {
         SysStaff* ss  = system->staff(staffIdx);
 
@@ -601,6 +605,12 @@ void SystemLayout::hideEmptyStaves(System* system, LayoutContext& ctx, bool isFi
                 && !(isFirstSystem && ctx.conf().styleB(Sid::dontHideStavesInFirstSystem))
                 && hideMode != Staff::HideMode::NEVER)) {
             bool hideStaff = true;
+            for (auto spanner : spanners) {
+                if (spanner.value->staff() == staff) {
+                    hideStaff = false;
+                    break;
+                }
+            }
             for (MeasureBase* m : system->measures()) {
                 if (!m->isMeasure()) {
                     continue;

src/engraving/rendering/stable/systemlayout.cpp

@@ -589,6 +589,10 @@ void SystemLayout::hideEmptyStaves(System* system, LayoutContext& ctx, bool isFi
     staff_idx_t staffIdx = 0;
     bool systemIsEmpty = true;
 
+    Fraction stick = system->measures().front()->tick();
+    Fraction etick = system->measures().back()->endTick();
+    auto spanners = ctx.dom().spannerMap().findOverlapping(stick.ticks(), etick.ticks());
+
     for (const Staff* staff : ctx.dom().staves()) {
         SysStaff* ss  = system->staff(staffIdx);
 
@@ -600,6 +604,12 @@ void SystemLayout::hideEmptyStaves(System* system, LayoutContext& ctx, bool isFi
                 && !(isFirstSystem && ctx.conf().styleB(Sid::dontHideStavesInFirstSystem))
                 && hideMode != Staff::HideMode::NEVER)) {
             bool hideStaff = true;
+            for (auto spanner : spanners) {
+                if (spanner.value->staff() == staff) {
+                    hideStaff = false;
+                    break;
+                }
+            }
             for (MeasureBase* m : system->measures()) {
                 if (!m->isMeasure()) {
                     continue;