feat: add line renderer / visualisations for box collidors as a test

tests/destrum_tests.cpp

@@ -23,6 +23,7 @@
 #include <destrum/Components/Animator.h>
 #include <destrum/Components/Physics/Rigidbody.h>
 #include <destrum/Graphics/Material.h>
+#include <destrum/Graphics/Managers/LineRenderingManager.h>
 
 namespace {
     class TestComponent final : public Component {
@@ -189,6 +190,29 @@ namespace {
               "RigidBody legacy alias must not be registered");
     }
 
+    void testLineRenderingManager()
+    {
+        auto& lineManager = LineRenderingManager::GetInstance();
+        lineManager.ClearLines();
+
+        lineManager.SubmitLine(
+            glm::vec3{0.0f},
+            glm::vec3{1.0f, 0.0f, 0.0f},
+            glm::vec4{1.0f, 0.0f, 0.0f, 1.0f});
+        lineManager.SubmitLine(Line{
+            .start = glm::vec3{1.0f},
+            .end = glm::vec3{2.0f},
+            .color = glm::vec4{0.0f, 1.0f, 0.0f, 1.0f},
+        });
+
+        check(lineManager.GetLines().size() == 2,
+              "line rendering manager must retain submitted lines");
+
+        lineManager.ClearLines();
+        check(lineManager.GetLines().empty(),
+              "line rendering manager must clear transient lines");
+    }
+
     void testAssetPathValidation()
     {
         const auto root = std::filesystem::temp_directory_path() / "destrum_asset_test";
@@ -469,6 +493,7 @@ int main()
     testEventRemoval();
     testComponentRemoval();
     testEngineComponentRegistration();
+    testLineRenderingManager();
     testAssetPathValidation();
     testLegacySceneLoad();
     testSceneLoadRollback();