Add support for Apple Silicon

-Update classes to read correct Apple Silicon CPU sensor
-Update project to compile a Universal 2 binary. Upgraded Sparkle to 2.1.0 as that was the latest and supports ARM64.
-Add MacBookPro18,1 to Machines.plist

Sparkle.framework/Versions/B/PrivateHeaders/SPUAppcastItemStateResolver.h

@@ -0,0 +1,37 @@
+//
+//  SPUAppcastItemStateResolver.h
+//  Sparkle
+//
+//  Created by Mayur Pawashe on 5/31/21.
+//  Copyright © 2021 Sparkle Project. All rights reserved.
+//
+
+#if __has_feature(modules)
+#if __has_warning("-Watimport-in-framework-header")
+#pragma clang diagnostic ignored "-Watimport-in-framework-header"
+#endif
+@import Foundation;
+#else
+#import <Foundation/Foundation.h>
+#endif
+
+#import <Sparkle/SUExport.h>
+
+NS_ASSUME_NONNULL_BEGIN
+
+@class SUStandardVersionComparator, SPUAppcastItemState;
+@protocol SUVersionComparison;
+
+/**
+ Private exposed class used to resolve Appcast Item properties that rely on external factors such as a host.
+ This resolver is used for constructing appcast items.
+ */
+SU_EXPORT @interface SPUAppcastItemStateResolver : NSObject
+
+- (instancetype)init NS_UNAVAILABLE;
+
+- (instancetype)initWithHostVersion:(NSString *)hostVersion applicationVersionComparator:(id<SUVersionComparison>)applicationVersionComparator standardVersionComparator:(SUStandardVersionComparator *)standardVersionComparator;
+
+@end
+
+NS_ASSUME_NONNULL_END

Sparkle.framework/Versions/B/PrivateHeaders/SPUInstallationType.h

@@ -0,0 +1,19 @@
+//
+//  SPUInstallationType.h
+//  Sparkle
+//
+//  Created by Mayur Pawashe on 7/24/16.
+//  Copyright © 2016 Sparkle Project. All rights reserved.
+//
+
+#ifndef SPUInstallationType_h
+#define SPUInstallationType_h
+
+#define SPUInstallationTypeApplication @"application" // the default installation type for ordinary application updates
+#define SPUInstallationTypeGuidedPackage @"package" // the preferred installation type for package installations
+#define SPUInstallationTypeInteractivePackage @"interactive-package" // the deprecated installation type; use guided package instead
+
+#define SPUInstallationTypesArray (@[SPUInstallationTypeApplication, SPUInstallationTypeGuidedPackage, SPUInstallationTypeInteractivePackage])
+#define SPUValidInstallationType(x) ((x != nil) && [SPUInstallationTypesArray containsObject:(NSString * _Nonnull)x])
+
+#endif /* SPUInstallationType_h */

Sparkle.framework/Versions/B/PrivateHeaders/SPUUserAgent+Private.h

@@ -0,0 +1,20 @@
+//
+//  SPUUserAgent+Private.h
+//  Sparkle
+//
+//  Created by Mayur Pawashe on 11/12/21.
+//  Copyright © 2021 Sparkle Project. All rights reserved.
+//
+
+#import <Foundation/Foundation.h>
+#import <Sparkle/SUExport.h>
+
+NS_ASSUME_NONNULL_BEGIN
+
+@class SUHost;
+
+SU_EXPORT NSString *SPUMakeUserAgentWithHost(SUHost *responsibleHost, NSString * _Nullable displayNameSuffix);
+
+SU_EXPORT NSString *SPUMakeUserAgentWithBundle(NSBundle *responsibleBundle, NSString * _Nullable displayNameSuffix);
+
+NS_ASSUME_NONNULL_END

Sparkle.framework/Versions/B/PrivateHeaders/SUAppcastItem+Private.h

@@ -0,0 +1,45 @@
+//
+//  SUAppcastItem+Private.h
+//  Sparkle
+//
+//  Created by Mayur Pawashe on 4/30/21.
+//  Copyright © 2021 Sparkle Project. All rights reserved.
+//
+
+#ifndef SUAppcastItem_Private_h
+#define SUAppcastItem_Private_h
+
+#if __has_feature(modules)
+#if __has_warning("-Watimport-in-framework-header")
+#pragma clang diagnostic ignored "-Watimport-in-framework-header"
+#endif
+@import Foundation;
+#else
+#import <Foundation/Foundation.h>
+#endif
+
+NS_ASSUME_NONNULL_BEGIN
+
+// Available in SPUAppcastItemStateResolver.h (a private exposed header)
+@class SPUAppcastItemStateResolver;
+
+@interface SUAppcastItem (Private) <NSSecureCoding>
+
+/**
+ Initializes with data from a dictionary provided by the RSS class and state resolver
+
+ This initializer method is intended to be marked "private" and discouraged from public usage.
+ This method is available however. Talk to us to describe your use case and if you need to construct appcast items yourself.
+ */
+- (nullable instancetype)initWithDictionary:(NSDictionary *)dict relativeToURL:(NSURL * _Nullable)appcastURL stateResolver:(SPUAppcastItemStateResolver *)stateResolver failureReason:(NSString * _Nullable __autoreleasing *_Nullable)error;
+
+/**
+ The DSA and EdDSA signatures along with their statuses.
+ */
+@property (readonly, nullable) SUSignatures *signatures;
+
+@end
+
+NS_ASSUME_NONNULL_END
+
+#endif /* SUAppcastItem_Private_h */

Sparkle.framework/Versions/B/PrivateHeaders/SUInstallerLauncher+Private.h

@@ -0,0 +1,29 @@
+//
+//  SUInstallerLauncher+Private.h
+//  SUInstallerLauncher+Private
+//
+//  Created by Mayur Pawashe on 8/21/21.
+//  Copyright © 2021 Sparkle Project. All rights reserved.
+//
+
+#ifndef SUInstallerLauncher_Private_h
+#define SUInstallerLauncher_Private_h
+
+#import <Sparkle/SUExport.h>
+
+// Chances are clients will need this too
+#import <Sparkle/SPUInstallationType.h>
+
+@class NSString;
+
+/**
+ Private API for determining if the system needs authorization access to update a bundle path
+ 
+ This API is not supported when used directly from a Sandboxed applications and will always return @c YES in that case.
+ 
+ @param bundlePath The bundle path to test if authorization is needed when performing an update that replaces this bundle.
+ @return @c YES if Sparkle thinks authorization is needed to update the @c bundlePath, otherwise @c NO.
+ */
+SU_EXPORT BOOL SPUSystemNeedsAuthorizationAccessForBundlePath(NSString *bundlePath);
+
+#endif /* SUInstallerLauncher_Private_h */