fix(build): 手动 patch SPM 链接 + 清孤儿文件让 Task 6 真正可编译

经过多轮 Xcode UI / SPM 解析失败,本 commit 合并以下修复:

pbxproj 手动 patch:
- 删除孤立的 mlx-swift XCRemoteSwiftPackageReference(版本 0.31.3 与
  mlx-swift-examples 2.29.1 锁定的 0.29.1..<0.30.0 冲突)
- 在 体己 target 加入 MLXLLM + MLXLMCommon 两个 product 依赖,绑定到
  mlx-swift-examples 包。补齐 PBXBuildFile + XCSwiftPackageProductDependency
  + packageProductDependencies + Frameworks build phase 4 处条目

LLMSession.swift 简化:
- 去掉 import MLX(避免需要把 mlx-swift transitive MLX/MLXFast/MLXNN 等
  5 个 product 也链上,大幅简化依赖)
- 移除 MLX.GPU.synchronize() 调用——研究笔记里建议的尾部同步对 AsyncStream
  数据正确性无影响,省一份直接 import 依赖

清理孤儿文件:
- 体己/AI/Theme.swift 和 体己/AI/TabBar.swift 是早期混乱中由出错的
  fix subagent 创建的占位 stub,跟 DesignSystem/Tokens.swift 重复声明
  enum Tj,导致 invalid redeclaration

附:Package.resolved 由 xcodebuild SPM resolve 生成,加入版本控制确保
团队成员锁定相同版本图。

** BUILD SUCCEEDED ** 验证通过(iPhone 17 Pro simulator)。

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

体己.xcodeproj/project.pbxproj

@@ -6,6 +6,11 @@
 	objectVersion = 77;
 	objects = {
 
+/* Begin PBXBuildFile section */
+		FEED000000000000DEAD0001 /* MLXLLM in Frameworks */ = {isa = PBXBuildFile; productRef = FEED000000000000DEAD0003 /* MLXLLM */; };
+		FEED000000000000DEAD0002 /* MLXLMCommon in Frameworks */ = {isa = PBXBuildFile; productRef = FEED000000000000DEAD0004 /* MLXLMCommon */; };
+/* End PBXBuildFile section */
+
 /* Begin PBXContainerItemProxy section */
 		5E463D092FC403BC0089145B /* PBXContainerItemProxy */ = {
 			isa = PBXContainerItemProxy;
@@ -52,6 +57,8 @@
 			isa = PBXFrameworksBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
+				FEED000000000000DEAD0001 /* MLXLLM in Frameworks */,
+				FEED000000000000DEAD0002 /* MLXLMCommon in Frameworks */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
@@ -112,6 +119,8 @@
 			);
 			name = "体己";
 			packageProductDependencies = (
+				FEED000000000000DEAD0003 /* MLXLLM */,
+				FEED000000000000DEAD0004 /* MLXLMCommon */,
 			);
 			productName = "体己";
 			productReference = 5E463CF92FC403BB0089145B /* 体己.app */;
@@ -195,6 +204,9 @@
 			);
 			mainGroup = 5E463CF02FC403BB0089145B;
 			minimizedProjectReferenceProxies = 1;
+			packageReferences = (
+				5E9A1F872FC43C9A0097DD29 /* XCRemoteSwiftPackageReference "mlx-swift-examples" */,
+			);
 			preferredProjectObjectVersion = 77;
 			productRefGroup = 5E463CFA2FC403BB0089145B /* Products */;
 			projectDirPath = "";
@@ -615,6 +627,30 @@
 			defaultConfigurationName = Release;
 		};
 /* End XCConfigurationList section */
+
+/* Begin XCRemoteSwiftPackageReference section */
+		5E9A1F872FC43C9A0097DD29 /* XCRemoteSwiftPackageReference "mlx-swift-examples" */ = {
+			isa = XCRemoteSwiftPackageReference;
+			repositoryURL = "https://github.com/ml-explore/mlx-swift-examples";
+			requirement = {
+				kind = upToNextMajorVersion;
+				minimumVersion = 2.29.1;
+			};
+		};
+/* End XCRemoteSwiftPackageReference section */
+
+/* Begin XCSwiftPackageProductDependency section */
+		FEED000000000000DEAD0003 /* MLXLLM */ = {
+			isa = XCSwiftPackageProductDependency;
+			package = 5E9A1F872FC43C9A0097DD29 /* XCRemoteSwiftPackageReference "mlx-swift-examples" */;
+			productName = MLXLLM;
+		};
+		FEED000000000000DEAD0004 /* MLXLMCommon */ = {
+			isa = XCSwiftPackageProductDependency;
+			package = 5E9A1F872FC43C9A0097DD29 /* XCRemoteSwiftPackageReference "mlx-swift-examples" */;
+			productName = MLXLMCommon;
+		};
+/* End XCSwiftPackageProductDependency section */
 	};
 	rootObject = 5E463CF12FC403BB0089145B /* Project object */;
 }