Internals: LowerBound: Use raw pointer typedefs, we never use iterator anywhere else in the codebase.

Demo: Typo.
C98 fix.

imgui_demo.cpp

@@ -4027,7 +4027,7 @@ void ShowExampleAppDocuments(bool* p_open)
 {
     static ExampleAppDocuments app;
 
-    if (!ImGui::Begin("Examples: Documents", p_open, ImGuiWindowFlags_MenuBar))
+    if (!ImGui::Begin("Example: Documents", p_open, ImGuiWindowFlags_MenuBar))
     {
         ImGui::End();
         return;