Canned Messages via InkHUD menu (#7096)

* Allow observers to respond to AdminMessage requests
Ground work for CannedMessage getters and setters

* Enable CannedMessage config in apps for InkHUD devices

* Migrate the InkHUD::Events AdminModule observer
Use the new AdminModule_ObserverData struct

* Bare-bones NicheGraphics util to access canned messages
Handles loading and parsing. Handle admin messages for setting and getting.

* Send canned messages via on-screen menu

* Change ThreadedMessageApplet from Observer to Module API
Allows us to intercept locally generated packets ('loopbackOK = true'), to handle outgoing canned messages.

* Fix: crash getting empty canned message string via Client API

* Move file into Utils subdir

* Move an include statement from .cpp to .h

* Limit strncpy size of dest, not source
Wasn't critical in ths specific case, but definitely a mistake.

src/graphics/niche/InkHUD/Events.cpp

@@ -4,14 +4,13 @@
 
 #include "RTC.h"
 #include "buzz.h"
-#include "modules/AdminModule.h"
 #include "modules/ExternalNotificationModule.h"
 #include "modules/TextMessageModule.h"
 #include "sleep.h"
 
 #include "./Applet.h"
 #include "./SystemApplet.h"
-#include "graphics/niche/FlashData.h"
+#include "graphics/niche/Utils/FlashData.h"
 
 using namespace NicheGraphics;
 
@@ -30,7 +29,7 @@ void InkHUD::Events::begin()
     rebootObserver.observe(&notifyReboot);
     textMessageObserver.observe(textMessageModule);
 #if !MESHTASTIC_EXCLUDE_ADMIN
-    adminMessageObserver.observe(adminModule);
+    adminMessageObserver.observe((Observable<AdminModule_ObserverData *> *)adminModule);
 #endif
 #ifdef ARCH_ESP32
     lightSleepObserver.observe(&notifyLightSleep);
@@ -193,14 +192,15 @@ int InkHUD::Events::onReceiveTextMessage(const meshtastic_MeshPacket *packet)
     return 0; // Tell caller to continue notifying other observers. (No reason to abort this event)
 }
 
-int InkHUD::Events::onAdminMessage(const meshtastic_AdminMessage *message)
+int InkHUD::Events::onAdminMessage(AdminModule_ObserverData *data)
 {
-    switch (message->which_payload_variant) {
+    switch (data->request->which_payload_variant) {
     // Factory reset
     // Two possible messages. One preserves BLE bonds, other wipes. Both should clear InkHUD data.
     case meshtastic_AdminMessage_factory_reset_device_tag:
     case meshtastic_AdminMessage_factory_reset_config_tag:
         eraseOnReboot = true;
+        *data->result = AdminMessageHandleResult::HANDLED;
         break;
 
     default: