Merge remote-tracking branch 'origin/develop' into feat-touch

# Conflicts:
#	freeink-sdk
#	lib/I18n/translations/slovak.yaml
#	platformio.ini
#	src/components/icons/bookmark.h

src/activities/reader/XtcReaderActivity.cpp

@@ -300,7 +300,19 @@ void XtcReaderActivity::renderPage() {
       }
     }
 
-    ReaderUtils::displayWithRefreshCycle(renderer, pagesUntilFullRefresh);
+    if (pagesUntilFullRefresh <= 1) {
+      // Periodic ghost cleanup: scrub via the normal path, then run the
+      // settle flavor of the grayscale base pass (DTM planes are equal after
+      // the display sync, so only the gentle reinforcement cells fire).
+      renderer.displayBuffer(HalDisplay::HALF_REFRESH);
+      renderer.preconditionGrayscale();
+      pagesUntilFullRefresh = SETTINGS.getRefreshFrequency();
+    } else {
+      // OEM grayscale pipeline base: differential "AA-pre-BW(mid)" update as
+      // the page turn on X3; plain FAST refresh on X4 (previous behavior).
+      renderer.displayGrayscaleBase(HalDisplay::FAST_REFRESH);
+      pagesUntilFullRefresh--;
+    }
 
     // Pass 2: LSB buffer - mark DARK gray only (XTH value 1)
     // In LUT: 0 bit = apply gray effect, 1 bit = untouched