Don't crash when fn key pressed on mac (workaround upstream issue)

src/main.zig

@@ -194,6 +194,16 @@ pub fn log(
 
 fn glfwErrorCallback(code: glfw.Error, desc: [:0]const u8) void {
     std.log.warn("glfw error={} message={s}", .{ code, desc });
+
+    // Workaround for: https://github.com/ocornut/imgui/issues/5908
+    // If we get an invalid value with "scancode" in the message we assume
+    // it is from the glfw key callback that imgui sets and we clear the
+    // error so that our future code doesn't crash.
+    if (code == glfw.Error.InvalidValue and
+        std.mem.indexOf(u8, desc, "scancode") != null)
+    {
+        glfw.errors.getError() catch {};
+    }
 }
 
 test {