4.B SharePanel: 替换字符占位为 imageset 图标

从 docs/res/Images.xcassets 拷贝 shareWechat / shareQQ / shareDouyin
三套 imageset（@1x/@2x/@3x）到 ylgamehall/Assets.xcassets/。SharePanel
按钮从"彩色圆 + 首字"改为 setImage + clipsToBounds + 等比缩放，未安装
平台改 alpha 灰显（与原 daoqi msext SharePanel.m:147 createButtonWithImage
同款写法）。

ylgamehall/ 是 PBXFileSystemSynchronizedRootGroup，无需手改 pbxproj。

ylgamehall/Assets.xcassets/shareDouyin.imageset/Contents.json

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

ylgamehall/Assets.xcassets/shareQQ.imageset/Contents.json

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

ylgamehall/Assets.xcassets/shareWechat.imageset/Contents.json

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