add isCollapsed validation on nested artboard advance method

If the nested artboard is collapsed (for example when it's under a solo) the advance method will return.
This helps prevent unused animations or state machines from running when hidden.

Diffs=
8f6b07395 add isCollapsed validation on nested artboard advance method (#6081)

Co-authored-by: hernan <hernan@rive.app>

.rive_head

diff --git a/.rive_head b/.rive_head
index 737da8c..cfd6bcc 100644
--- a/.rive_head
+++ b/.rive_head
@@ -1 +1 @@
-c5cde614bdb0de792c0bb074185f6ff51b1ff954
+8f6b07395cd5a595cd8cb96b6692bc46bb5b8f28

src/nested_artboard.cpp

diff --git a/src/nested_artboard.cpp b/src/nested_artboard.cpp
index f4ab1c3..25bd218 100644
--- a/src/nested_artboard.cpp
+++ b/src/nested_artboard.cpp
@@ -123,7 +123,7 @@
 
 bool NestedArtboard::advance(float elapsedSeconds)
 {
-    if (m_Artboard == nullptr)
+    if (m_Artboard == nullptr || isCollapsed())
     {
         return false;
     }

test/assets/solos_with_nested_artboards.riv

diff --git a/test/assets/solos_with_nested_artboards.riv b/test/assets/solos_with_nested_artboards.riv
new file mode 100644
index 0000000..6c8e64b
--- /dev/null
+++ b/test/assets/solos_with_nested_artboards.riv
Binary files differ

test/nested_artboard.cpp

diff --git a/test/nested_artboard.cpp b/test/nested_artboard.cpp
new file mode 100644
index 0000000..2ce4939
--- /dev/null
+++ b/test/nested_artboard.cpp
@@ -0,0 +1,39 @@
+#include <rive/solo.hpp>
+#include <rive/nested_artboard.hpp>
+#include <rive/shapes/rectangle.hpp>
+#include <rive/shapes/shape.hpp>
+#include <rive/animation/state_machine_instance.hpp>
+#include <rive/animation/nested_linear_animation.hpp>
+#include <rive/animation/nested_state_machine.hpp>
+#include "rive_file_reader.hpp"
+#include "rive_testing.hpp"
+#include <catch.hpp>
+#include <cstdio>
+#include <iostream>
+
+TEST_CASE("collapsed nested artboards do not advance", "[solo]")
+{
+    auto file = ReadRiveFile("../../test/assets/solos_with_nested_artboards.riv");
+
+    auto artboard = file->artboard("main-artboard")->instance();
+    artboard->advance(0.0f);
+    auto solos = artboard->find<rive::Solo>();
+    REQUIRE(solos.size() == 1);
+    auto stateMachine = artboard->stateMachineAt(0);
+    stateMachine->advanceAndApply(0.0f);
+    REQUIRE(stateMachine->needsAdvance() == true);
+    artboard->advance(0.75f);
+    // Testing whether the squares have moved in the artboard is an indirect way
+    // if checking whether the time of each artboard has advanced
+    // Unfortunately there is no way of accessing the time of the animations directly
+    auto redNestedArtboard = stateMachine->artboard()->find<rive::NestedArtboard>("red-artboard");
+    auto redNestedArtboardArtboard = redNestedArtboard->artboard();
+    auto movingShapes = redNestedArtboardArtboard->find<rive::Shape>();
+    auto redRect = movingShapes.at(0);
+    REQUIRE(redRect->x() > 50);
+    auto greenNestedArtboard = stateMachine->artboard()->find<rive::NestedArtboard>("green-artboard");
+    auto greenNestedArtboardArtboard = greenNestedArtboard->artboard();
+    auto greenMovingShapes = greenNestedArtboardArtboard->find<rive::Shape>();
+    auto greenRect = greenMovingShapes.at(0);
+    REQUIRE(greenRect->x() == 50);
+}
\ No newline at end of file