fix: crash in LAN mode when the printer type is not known yet (#16191)

* fix: crash in LAN mode when the printer type is not known yet

InputIpAddressDialog::set_machine_obj() built the help image name from
the printer config with no fallback. If the printer type is empty or
unknown, for example before the first push_all arrives on a flaky LAN
link, the lookup returns "" and create_scaled_bitmap("_en") throws.
The dialog is opened by the "LAN Connection Failed" handlers in
MediaPlayCtrl and MediaFilePanel, where nothing catches the exception,
so the app crashes.

Use input_access_code_x1 when there is no image, and the _cn image for
zh_CN, the same as ConnectPrinterDialog::init_bitmap().

Ported from Bambu Studio 52ca2ec5d1.

* fix: return an empty bitmap for an empty icon name

create_scaled_bitmap() threw when a caller passed an empty name. That
happens when a printer config lookup has no entry, for example in
AMSSetting::update_ams_img() for a printer type with no AMS image.
Log an error and return wxNullBitmap instead.

Ported from Bambu Studio 52ca2ec5d1.

src/slic3r/GUI/wxExtensions.cpp

@@ -456,6 +456,13 @@ wxBitmap create_scaled_bitmap(  const std::string& bmp_name_in,
                                 const vector<std::string>& array_new_color/* = vector<std::string>*/)//used for semi transparent material)
 {
     static Slic3r::GUI::BitmapCache cache;
+
+    // An empty name means the caller's icon lookup failed
+    if (bmp_name_in.empty() || bmp_name_in == ".png") {
+        BOOST_LOG_TRIVIAL(error) << __FUNCTION__ << ": empty bitmap name";
+        return wxNullBitmap;
+    }
+
     if (bitmap2) {
         return create_scaled_bitmap2(bmp_name_in, cache, win, px_cnt, grayscale, resize, array_new_color);
     }