Register more glyph ranges supported by Roboto

Adds support for Polish, makes Russian use a default font

src/frontend-common/imgui_styles.cpp

@@ -61,6 +61,26 @@ void ImGui::StyleColorsDarker(ImGuiStyle* dst)
 
 void ImGui::AddRobotoRegularFont(float size /*= 15.0f*/)
 {
+  static const ImWchar ranges[] = {
+    // Basic Latin + Latin Supplement + Central European diacritics
+    0x0020,
+    0x017F,
+
+    // Cyrillic + Cyrillic Supplement
+    0x0400,
+    0x052F,
+
+    // Cyrillic Extended-A
+    0x2DE0,
+    0x2DFF,
+
+    // Cyrillic Extended-B
+    0xA640,
+    0xA69F,
+
+    0,
+  };
+
   ImGui::GetIO().Fonts->AddFontFromMemoryCompressedTTF(s_font_roboto_regular_compressed_data,
-                                                       s_font_roboto_regular_compressed_size, size);
+                                                       s_font_roboto_regular_compressed_size, size, nullptr, ranges);
 }