Add ResumeBackup functor

Sources/ElixxirDAppsSDK/Functors/ResumeBackup.swift

+import Bindings
+import XCTestDynamicOverlay
+
+public struct ResumeBackup {
+  public var run: (Int, Int, UpdateBackupFunc) throws -> Backup
+
+  public func callAsFunction(
+    e2eId: Int,
+    udId: Int,
+    callback: UpdateBackupFunc
+  ) throws -> Backup {
+    try run(e2eId, udId, callback)
+  }
+}
+
+extension ResumeBackup {
+  public static let live = ResumeBackup { e2eId, udId, callback in
+    var error: NSError?
+    let bindingsBackup = BindingsResumeBackup(
+      e2eId,
+      udId,
+      callback.makeBindingsUpdateBackupFunc(),
+      &error
+    )
+    if let error = error {
+      throw error
+    }
+    guard let bindingsBackup = bindingsBackup else {
+      fatalError("BindingsResumeBackup returned `nil` without providing error")
+    }
+    return .live(bindingsBackup)
+  }
+}
+
+extension ResumeBackup {
+  public static let unimplemented = ResumeBackup(
+    run: XCTUnimplemented("\(Self.self)")
+  )
+}