* new ui/DisplayDriver classes (just SSD1306Display impl for now)

* companion radio: now with optional UITask (enabled by DISPLAY_CLASS config in target/env)

examples/companion_radio/UITask.h

@@ -0,0 +1,22 @@
+#pragma once
+
+#include <helpers/ui/DisplayDriver.h>
+
+class UITask {
+  DisplayDriver* _display;
+  unsigned long _next_read, _next_refresh, _auto_off;
+  int _prevBtnState;
+  const char* _node_name;
+  const char* _build_date;
+  char _origin[62];
+  char _msg[80];
+
+  void renderCurrScreen();
+public:
+  UITask(DisplayDriver& display) : _display(&display) { _next_read = _next_refresh = 0; }
+  void begin(const char* node_name, const char* build_date);
+
+  void clearMsgPreview();
+  void showMsgPreview(uint8_t path_len, const char* from_name, const char* text);
+  void loop();
+};