Refactored events (#621)

Event handling:

- Added unified event handling for application, system, and Wi‑Fi events.
- Updated all apps to reflect event handling changes

Wi-Fi:

- Refactored event handling from listener interface to task & event group.
- Added direct Wi‑Fi radio controls and improved event subscriptions.
- Wi‑Fi screens now refresh asynchronously and handle unavailable devices more gracefully.
- Enabled Wi‑Fi by default on in dts files, but radio on/off is still done by code. The main reason was reliable event subscription and consistent devicetree states.
- Improved Wi‑Fi shutdown cleanup and radio-state handling.

Other:
- Renamed the Kernel Display app to Display.

Documentation/ideas.md

@@ -11,11 +11,15 @@
 
 ## Higher Priority
 
-- AppEventSubscription, SystemEventSubscription: should use TaskHandle_t notification. That way, there can be a single wait event for a task instead of X separate ones with each their timeout.
+- lvgl file lock won't work with display vs sdcard when lvgl is stopped (external app bug risk)
+- Apps should be able to specify stack size in their manifest
+- Apps currently have a `Context` object with an `appInstanceId` in it, purely for being able to close the app.
+  Change it so that the app has its own termination signal that it waits for in the loop, it should subscribe to the event group.
+- stopAppFromToolbar() in Tactility.cpp stops the top-most app. Change it so the toolbar knows for which app id it is created, so it can rely on that.
+- Warn if file operations are done from prohibited tasks (e.g. lvgl task)
 - AppHubApp: Prevent download callbacks from accessing a destroyed view.
 - Move USB host task stacks to SPIRAM when available: esp32_usbhost*.cpp
-- wifi: wifi_add_event_callback() and wifi_remove_event_callback() should be replaced by a subscribe/await pattern like system events.
-  When that's changed reduce LVGL callstack size in Tactility.cpp run()
+- Get rid of WiFi service (Wifi.cpp/h) in Tactility.cpp
 - Make it more clear to end-users that an SD card is required to run Tactility
 - Make it possible to override stack size for an app via config file (loaded at boot), and make it possible to set preferred memory location (e.g. internal/external)
 - Wrap file operations like fopen/fclose with file_mutex