Add setInterOpNumThreads to ORTSessionOptions

Wraps the C API's SetInterOpNumThreads, mirroring the existing
setIntraOpNumThreads binding.

Automated-By: Claude Fable 5

swift/OnnxRuntimeBindings/ORTInterface.swift

@@ -405,6 +405,7 @@ public final class ORTSession {
 public final class ORTSessionOptions {
     public private(set) var executionProviders: [(name: String, options: [String: String])] = []
     public private(set) var intraOpNumThreads: Int32 = 0
+    public private(set) var interOpNumThreads: Int32 = 0
     public private(set) var graphOptimizationLevel: ORTGraphOptimizationLevel = .all
     public private(set) var optimizedModelFilePath: String?
     public private(set) var logID: String?
@@ -470,6 +471,14 @@ public final class ORTSessionOptions {
         intraOpNumThreads = count
     }
 
+    public func setInterOpNumThreads(_ count: Int32) throws {
+        try ORTNative.check(
+            ORTNative.api.pointee.SetInterOpNumThreads?(handle, Int32(count)),
+            action: "SetInterOpNumThreads"
+        )
+        interOpNumThreads = count
+    }
+
     public func setGraphOptimizationLevel(_ level: ORTGraphOptimizationLevel) throws {
         try ORTNative.check(
             ORTNative.api.pointee.SetSessionGraphOptimizationLevel?(handle, level.native),