add extended ascii

src/font.h

@@ -14,7 +14,7 @@ class Font
 public:
     int w = 512;
     int h = 512;
-    const int num_chars = 96;
+    const int num_chars = 256-32;
     const int start_char = 32;
     // {mix, max}
     glm::vec4 bounds{ 0 };