use partial draw

src/dreader_hal/display/it8951.py

@@ -176,8 +176,8 @@ class IT8951DisplayDriver:
         # Prepare image for e-ink
         prepared_image = self._prepare_image(image)
 
-        # Update frame buffer
-        self.display.frame_buf = prepared_image
+        # Update frame buffer using paste (more reliable than direct assignment)
+        self.display.frame_buf.paste(prepared_image, (0, 0))
 
         # Increment refresh counter
         self._refresh_count += 1
@@ -316,9 +316,15 @@ class IT8951DisplayDriver:
         if hasattr(self.display, 'epd') and self.auto_sleep:
             self.display.epd.run()
 
-        # Use partial update for efficiency
-        # IT8951 library tracks what changed and only updates that region
-        self.display.draw_partial(display_mode)
+        # Use full refresh for INIT mode (clears ghosting) or first few refreshes
+        # Use partial refresh for fast updates
+        if display_mode == DisplayModes.INIT or self._refresh_count <= 2:
+            # Full refresh - more reliable for initial displays
+            self.display.draw_full(display_mode)
+        else:
+            # Partial update for efficiency
+            # IT8951 library tracks what changed and only updates that region
+            self.display.draw_partial(display_mode)
 
     async def set_brightness(self, level: int) -> None:
         """