Make Linux Bundle concurrency safe for Swift 6.

Signed-off-by: furby™ <devs@wabi.foundation>

Package.resolved

@@ -1,5 +1,5 @@
 {
-  "originHash" : "574e70c31d2f9e918e37ad66f2b3778e74a498b10fbcf408505b90a3b7d2c027",
+  "originHash" : "3abc8be558cfafce9b6bfe2e4459c53be9490bc02aa0976397031b7ca60ab377",
   "pins" : [
     {
       "identity" : "icu",
@@ -15,8 +15,8 @@
       "kind" : "remoteSourceControl",
       "location" : "https://github.com/wabiverse/MetaverseKit",
       "state" : {
-        "branch" : "main",
-        "revision" : "8cf6729a950092be3d3d627964731c3b974531b8"
+        "revision" : "e23651486710c0a442c70adc709acdf91c0c74ff",
+        "version" : "1.9.0"
       }
     },
     {

Package.swift

@@ -280,7 +280,7 @@ let package = Package(
     // prepare for SwiftCrossUI, for a cross-platform UsdView.
     // .package(url: "https://github.com/stackotter/swift-cross-ui", revision: "5c5d8c8"),
     .package(url: "https://github.com/wabiverse/icu.git", from: "76.1.2"),
-    .package(url: "https://github.com/wabiverse/MetaverseKit", branch: "main"),
+    .package(url: "https://github.com/wabiverse/MetaverseKit", from: "1.9.0"),
     .package(url: "https://github.com/swiftlang/swift-syntax.git", from: "600.0.1"),
     .package(url: "https://github.com/swiftlang/swift-docc-plugin", from: "1.4.3"),
     .package(url: "https://github.com/apple/swift-log.git", from: "1.5.3"),

Sources/PixarUSD/Bundle.swift

@@ -20,28 +20,22 @@ import Rainbow
   /**
    * On Linux there is no ``Foundation.Bundle``, so we create one.
    */
-  public struct Bundle
+  public final class Bundle: Sendable
   {
     public static let main = Bundle()
+
+    public let resourcePath: String?
+
     private init()
     {
       resourcePath = "/" + Arch.getExecutablePath().split(separator: "/").dropLast().joined(separator: "/")
-
       Msg.logger.log(level: .info, "Bundle path: \(resourcePath ?? "")")
     }
 
-    public var resourcePath: String?
-
     public init?(path: String)
     {
-      if FileManager.default.fileExists(atPath: path, isDirectory: nil)
-      {
-        resourcePath = path
-      }
-      else
-      {
-        return nil
-      }
+      guard FileManager.default.fileExists(atPath: path, isDirectory: nil) else { return nil }
+      resourcePath = path
     }
   }
 #endif /* os(Linux) */