修复agent_service的user_portrait包路径错误

Package.swift 第19行原来引用 ../../../music_service/ios/user_portrait
（这个目录不存在），实际应该是 ../../../user_portrait/ios/user_portrait。

之前 Xcode 可能蒙混过了，但 Xcode 16 + Swift 6 严格解析时撞上空 Package
导致 IDESPMWorkspaceDelegate 数组索引崩溃，整个 workspace 加载失败。

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

local_plugins/agent_service/ios/agent_service/Package.swift

@@ -16,7 +16,7 @@ let package = Package(
     .package(path: "../../../chat_storage/ios/chat_storage"),
     .package(path: "../../../location_service/ios/location_service"),
     .package(path: "../../../music_service/ios/music_service"),
-    .package(path: "../../../music_service/ios/user_portrait"),
+    .package(path: "../../../user_portrait/ios/user_portrait"),
     .package(path: "../../../qq_music/ios/qq_music"),
   ],
   targets: [