fix: update NetSurf port & montauk frontend to use new paths for fonts and icons

www-client/netsurf/compat/stb_image_impl.c

@@ -0,0 +1,18 @@
+#include <stdlib.h>
+#include <string.h>
+
+#define STBI_NO_BMP
+#define STBI_NO_PSD
+#define STBI_NO_TGA
+#define STBI_NO_GIF
+#define STBI_NO_HDR
+#define STBI_NO_PIC
+#define STBI_NO_PNM
+#define STBI_NO_LINEAR
+#define STBI_NO_STDIO
+#define STBI_NO_THREAD_LOCALS
+#define STBI_MALLOC(sz) malloc(sz)
+#define STBI_FREE(p) free(p)
+#define STBI_REALLOC(p, newsz) realloc(p, newsz)
+#define STB_IMAGE_IMPLEMENTATION
+#include <gui/stb_image.h>