Add readable pastel tile backgrounds and refresh setup documentation

components/smart_display/tile_palette.h

@@ -0,0 +1,19 @@
+#pragma once
+#include <cstdint>
+#include <string>
+
+namespace tile_palette {
+// Match the editor palette; all backgrounds are chosen for dark text.
+inline uint32_t color(const std::string &name) {
+  if(name=="red")return 0xFADADD;
+  if(name=="orange")return 0xFFE1C6;
+  if(name=="yellow")return 0xFFF0C2;
+  if(name=="green")return 0xD9EEDC;
+  if(name=="mint")return 0xD5F0EA;
+  if(name=="blue")return 0xD9EAFB;
+  if(name=="purple")return 0xE9DDF5;
+  if(name=="pink")return 0xF7DDEC;
+  if(name=="gray")return 0xE5E7EB;
+  return 0;  // Automatic/default, including unknown future palette names.
+}
+}