Add InkHUD driver for WeAct Studio 4.2" display module (#6384)

* chore: todo.txt

* chore: InkHUD documentation
Word salad for maintainers

* refactor: don't init system applets using onActivate
System applets cannot be deactivated, so we will avoid using onActivate / onDeactivate methods entirely.

* chore: update the example applets

* fix: SSD16XX reset pulse
Allow time for controller IC to wake. Aligns with manufacturer's suggestions.
T-Echo button timing adjusted to prevent bouncing as a result(?) of slightly faster refreshes.

* fix: allow timeout if display update fails
Result is not graceful, but avoids total display lockup requiring power cycle.
Typical cause of failure is poor wiring / power supply.

* fix: improve display health on shutdown
Two extra full refreshes, masquerading as a "shutting down" screen. One is drawn white-on-black, to really shake the pixels up.

* feat: driver for display HINK_E042A87
As of Feb. 2025, these panels are used for "WeActStudio 4.2in B&W" display modules.

* fix: inkhud rotation should default to 0

* Revert "chore: todo.txt"

This reverts commit bea7df44a7cbf2f92e8c67c965e53d26a7885b11.

* fix: more generous timeout for display updates
Previously this was tied to the expected duration of the update, but this didn't account for any delay if our polling thread got held up by an unrelated firmware task.

* fix: don't use the full shutdown screen during reboot

* fix: cooldown period during the display shutdown display sequence
Observed to prevent border pixels from being locked in place with some residual charge?

src/graphics/niche/InkHUD/Applets/Examples/NewMsgExample/NewMsgExampleApplet.cpp

@@ -4,11 +4,12 @@
 
 using namespace NicheGraphics;
 
-// We configured MeshModule API to call this method when we receive a new text message
+// We configured the Module API to call this method when we receive a new text message
 ProcessMessage InkHUD::NewMsgExampleApplet::handleReceived(const meshtastic_MeshPacket &mp)
 {
 
     // Abort if applet fully deactivated
+    // Don't waste time: we wouldn't be rendered anyway
     if (!isActive())
         return ProcessMessage::CONTINUE;
 
@@ -25,7 +26,7 @@ ProcessMessage InkHUD::NewMsgExampleApplet::handleReceived(const meshtastic_Mesh
         requestUpdate();
     }
 
-    // Tell MeshModule API to continue informing other firmware components about this message
+    // Tell Module API to continue informing other firmware components about this message
     // We're not the only component which is interested in new text messages
     return ProcessMessage::CONTINUE;
 }