Phase 4.F：微信截图分享 type=2 / 远端图分享 type=其它

按 msext gameController.m:637-678 字面行为，WechatShare 按 content.type
分发：
- type=1 → shareLink（已有）
- type=2 → captureScreenshot → JPEG 0.6 + thumb 0.4x → shareImage
- type=其它 → downloadRemote(URL) → JPEG 0.9 + thumb 0.4x → shareImage

新增：
- ImageProvider.scaledThumb(_:scale:)：等价 msext FuncPublic
  imageByScalingAndCroppingForSize 0.4x 缩放；微信 SDK setThumbImage:
  内部再压到 32KB
- WeChatManager.ShareImage 结构 + shareImage(_:scene:) 异步包装
  （WXImageObject + WXMediaMessage.setThumbImage，FIFO 串行复用 sharePending）

契约：与 type=1 一致，调成功 → sharesuccess 反向 callback（success/cancelled
都发）；errCode=-2 → cancelled；其它 errCode → failed。

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

ylgamehall/Source/Share/WechatShare.swift

@@ -9,6 +9,7 @@
 //
 
 import Foundation
+import UIKit
 
 #if canImport(WechatOpenSDK)
 import WechatOpenSDK
@@ -37,18 +38,44 @@ public final class WechatShare: SharePlatform {
             return .notInstalled(platform: name)
         }
         let wxScene: WeChatManager.ShareScene = (scene == .timeline) ? .timeline : .session
-        // 当前仅链接分享（type == "1"）走真实 SDK；截图 / 远端图分享待 Phase 4.F 接入
-        // WXImageObject + WXMediaMessage.thumbData
         do {
-            try await WeChatManager.shared.shareLink(
-                .init(
-                    url: content.webpageUrl,
-                    title: content.title,
-                    desc: content.desc,
-                    thumbnailURL: nil   // type=2/3 缩略图待 Phase 4.F
-                ),
-                scene: wxScene
-            )
+            switch content.type {
+            case "1":
+                // 链接分享（msext gameController.m:613-635）
+                try await WeChatManager.shared.shareLink(
+                    .init(
+                        url: content.webpageUrl,
+                        title: content.title,
+                        desc: content.desc,
+                        thumbnailURL: nil
+                    ),
+                    scene: wxScene
+                )
+            case "2":
+                // 截图分享（msext gameController.m:637-658）
+                let shot = try ImageProvider.captureScreenshot()
+                guard let imageData = shot.jpegData(compressionQuality: 0.6) else {
+                    return .failed(reason: "screenshot JPEG encode failed")
+                }
+                let thumb = ImageProvider.scaledThumb(shot)
+                try await WeChatManager.shared.shareImage(
+                    .init(imageData: imageData, thumb: thumb),
+                    scene: wxScene
+                )
+            default:
+                // 远端图分享（msext gameController.m:659-680：type 是其它值就当 URL 远端图）
+                let remote = try await ImageProvider.downloadRemote(content.webpageUrl)
+                // msext 直接用原始 data 作为大图；这里 UIImage 已是 decode 后的，
+                // 用 jpegData 重新编码维持等价（避免持有未压缩的原始字节膨胀）。
+                guard let imageData = remote.jpegData(compressionQuality: 0.9) else {
+                    return .failed(reason: "remote image JPEG encode failed")
+                }
+                let thumb = ImageProvider.scaledThumb(remote)
+                try await WeChatManager.shared.shareImage(
+                    .init(imageData: imageData, thumb: thumb),
+                    scene: wxScene
+                )
+            }
             return .success
         } catch let WeChatError.shareFailed(errCode) {
             if errCode == -2 { return .cancelled }