Build input file cannot be found: '.../CAuditToken.o' (#908)

Resolves a build error in Xcode:
> Build input file cannot be found: '.../CAuditToken.o'. Did you forget
to declare this file as an output of a script phase or custom build rule
which produces it?

Author: dkovba

Package.swift

@@ -375,14 +375,14 @@ let package = Package(
                 .define("RELEASE_VERSION", to: "\"\(releaseVersion)\""),
                 .define("BUILDER_SHIM_VERSION", to: "\"\(builderShimVersion)\""),
             ],
-            linkerSettings: [
-                .linkedLibrary("bsm")
-            ]
         ),
         .target(
             name: "CAuditToken",
             dependencies: [],
-            publicHeadersPath: "include"
+            publicHeadersPath: "include",
+            linkerSettings: [
+                .linkedLibrary("bsm")
+            ]
         ),
     ]
 )

Sources/CAuditToken/AuditToken.c

@@ -0,0 +1,17 @@
+//===----------------------------------------------------------------------===//
+// Copyright © 2025 Apple Inc. and the container project authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//   https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//===----------------------------------------------------------------------===//
+
+// This file is required for Xcode to generate `CAuditToken.o`.