[AltStoreCore] Adds Pledge, PledgeReward, and PledgeTier

Allows us to cache pledges for current user, which can be used to determine if user has access to Patreon-only apps.

AltStoreCore/Model/Patreon/Pledge.swift

@@ -0,0 +1,54 @@
+//
+//  Pledge.swift
+//  AltStoreCore
+//
+//  Created by Riley Testut on 10/24/23.
+//  Copyright © 2023 Riley Testut. All rights reserved.
+//
+
+import Foundation
+import CoreData
+
+@objc(Pledge)
+public class Pledge: NSManagedObject, Fetchable
+{
+    /* Properties */
+    @NSManaged public private(set) var identifier: String
+    @NSManaged public private(set) var campaignURL: URL
+    
+    @nonobjc public var amount: Decimal { _amount as Decimal }
+    @NSManaged @objc(amount) private var _amount: NSDecimalNumber
+    
+    /* Relationships */
+    @NSManaged public private(set) var account: PatreonAccount?
+    
+    @nonobjc public var tiers: Set<PledgeTier> { _tiers as! Set<PledgeTier> }
+    @NSManaged @objc(tiers) internal var _tiers: NSSet
+    
+    @nonobjc public var rewards: Set<PledgeReward> { _rewards as! Set<PledgeReward> }
+    @NSManaged @objc(rewards) internal var _rewards: NSSet
+    
+    private override init(entity: NSEntityDescription, insertInto context: NSManagedObjectContext?)
+    {
+        super.init(entity: entity, insertInto: context)
+    }
+    
+    init?(patron: PatreonAPI.Patron, context: NSManagedObjectContext)
+    {
+        guard let amount = patron.pledgeAmount, let campaignURL = patron.campaign?.url else { return nil }
+        
+        super.init(entity: Pledge.entity(), insertInto: context)
+        
+        self.identifier = patron.identifier
+        self._amount = amount as NSDecimalNumber
+        self.campaignURL = campaignURL
+    }
+}
+
+public extension Pledge
+{
+    @nonobjc class func fetchRequest() -> NSFetchRequest<Pledge>
+    {
+        return NSFetchRequest<Pledge>(entityName: "Pledge")
+    }
+}