fix: rotate portrait renders to EPD-native byte layout

The .bin file for portrait orientation was packed as 480-pixel rows ×
800 rows, but firmware streams blindly at 800×480 (the EPD's native
scan order). Both layouts hit the same 192000-byte total, so the size
guard in epd_draw_image_with_border passed and the row-stride mismatch
showed up on the panel as the photo tiling/repeating.

Renderer now rotates the cropped photo 90° CW before dithering when
orientation is portrait, so the packed bytes always match the EPD's
800-pixel scan order. Firmware stays orientation-unaware (per the
"ESP32 never transforms images" decision in webApp/CLAUDE.md). Preview
decoder rotates -90° on the way out so the in-browser frame preview
stays upright.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/Enum/DeviceModel.php

@@ -17,4 +17,16 @@ enum DeviceModel: string
     {
         return $orientation === Orientation::Portrait ? 800 : 480;
     }
+
+    /** EPD's hardware scan-row width — independent of user orientation. */
+    public function nativeWidth(): int
+    {
+        return 800;
+    }
+
+    /** EPD's hardware scan-row count — independent of user orientation. */
+    public function nativeHeight(): int
+    {
+        return 480;
+    }
 }