Add main application logic and touch handling functionality

- Implemented main application entry point in main.cpp, initializing queues and event groups.
- Created TouchHandler and EInkTouchHandler classes for handling touch events.
- Added a minimal event loop for touch processing in touch.cpp.
- Introduced unit tests for the hello world application in pytest_hello_world.py.
- Added configuration files for CI and Wokwi support.
- Created empty header files for network and UI modules.

main/display/display.h

@@ -0,0 +1,42 @@
+#include "info/info.h"
+
+typedef void (*shutdown_display_handlerFunc)(void);
+typedef void (*restart_display_handlerFunc)(void);
+
+class DisplayHandler {
+public:
+  DisplayHandler(QueueHandle_t touch_queue, SemaphoreHandle_t lvgl_mutex);
+  // the system_event_group is used to set display-ready bit
+  virtual void init(EventGroupHandle_t system_event_group) = 0;
+  virtual void start_event_loop() = 0;
+  // get a handler to perform display shutdown cleanup, this is called after event loop ends and DisplayHandler is deleted
+  virtual shutdown_display_handlerFunc get_shutdown_display_handler() = 0;
+  virtual restart_display_handlerFunc get_restart_display_handler() = 0;
+  virtual ~DisplayHandler() = 0;
+
+private:
+  DisplayHandler(const DisplayHandler&) = delete;
+  DisplayHandler& operator=(const DisplayHandler&) = delete;
+};
+
+class EInkDisplayHandler : public DisplayHandler {
+public:
+  EInkDisplayHandler(QueueHandle_t touch_queue, SemaphoreHandle_t lvgl_mutex);
+  void init(EventGroupHandle_t system_event_group) override;
+  void start_event_loop() override;
+  shutdown_display_handlerFunc get_shutdown_display_handler() override;
+  restart_display_handlerFunc get_restart_display_handler() override;
+  ~EInkDisplayHandler() override;
+
+private:
+  // Task adapter used for FreeRTOS task creation. It forwards to the
+  // instance `run_event_loop()` method using the `this` pointer passed
+  // as the task parameter.
+  static void task_adapter(void* arg);
+
+  // Instance method that implements the display task loop.
+  void run_event_loop();
+  // prevent copying
+  EInkDisplayHandler(const EInkDisplayHandler&) = delete;
+  EInkDisplayHandler& operator=(const EInkDisplayHandler&) = delete;
+};