fix #551: Make finding broadcasts by name case insensitive

Matches Scratch behavior.

Author: adazem009

src/engine/internal/engine.cpp

@@ -1083,7 +1083,14 @@ std::shared_ptr<Broadcast> Engine::broadcastAt(int index) const
 
 int Engine::findBroadcast(const std::string &broadcastName) const
 {
-    auto it = std::find_if(m_broadcasts.begin(), m_broadcasts.end(), [broadcastName](std::shared_ptr<Broadcast> broadcast) { return broadcast->name() == broadcastName; });
+    std::string lowercaseName = broadcastName;
+    std::transform(lowercaseName.begin(), lowercaseName.end(), lowercaseName.begin(), ::tolower);
+
+    auto it = std::find_if(m_broadcasts.begin(), m_broadcasts.end(), [lowercaseName](std::shared_ptr<Broadcast> broadcast) {
+        std::string name = broadcast->name();
+        std::transform(name.begin(), name.end(), name.begin(), ::tolower);
+        return name == lowercaseName;
+    });
 
     if (it == m_broadcasts.end())
         return -1;

test/engine/engine_test.cpp

@@ -1289,6 +1289,8 @@ TEST(EngineTest, Broadcasts)
     ASSERT_EQ(engine.findBroadcast("message1"), 0);
     ASSERT_EQ(engine.findBroadcast("message2"), 1);
     ASSERT_EQ(engine.findBroadcast("Test"), 2);
+    ASSERT_EQ(engine.findBroadcast("MessAge2"), 1);
+    ASSERT_EQ(engine.findBroadcast("tEst"), 2);
 
     ASSERT_EQ(engine.findBroadcastById("d"), -1);
     ASSERT_EQ(engine.findBroadcastById("a"), 0);