feat: custom ghost icon + move Ghostgram Settings under Кошелёк

- Generated ghost icon for Ghostgram Settings menu item
- Added GhostgramSettings.imageset (@1x/@2x/@3x PNG)
- Moved Ghostgram Settings from .advanced section (between Privacy &
  Chat Settings) into .myProfile section, placing it directly after
  'Мой профиль' (visually appears just below Кошелёк in the list)
- Replaced generic Appearance icon with new custom ghost icon

submodules/TelegramUI/Images.xcassets/Settings/Menu/GhostgramSettings.imageset/Contents.json

@@ -0,0 +1,23 @@
+{
+    "images": [
+        {
+            "filename": "ghost_settings.png",
+            "idiom": "universal",
+            "scale": "1x"
+        },
+        {
+            "filename": "ghost_settings@2x.png",
+            "idiom": "universal",
+            "scale": "2x"
+        },
+        {
+            "filename": "ghost_settings@3x.png",
+            "idiom": "universal",
+            "scale": "3x"
+        }
+    ],
+    "info": {
+        "author": "xcode",
+        "version": 1
+    }
+}