feat(account): add managed credits and cloud gateway

Introduce optional Apple account-backed credits with scoped gateway access while preserving local and BYOK paths. Refresh assistant behavior, tests, privacy disclosures, docs, and the website for the 2.0 experience.

OSGKeyboardShared/Typing/PinyinNextKeyResolver.swift

@@ -73,8 +73,7 @@ public enum PinyinNextKeyResolver {
     private static func collectNext(prefix: String, into result: inout Set<Character>) {
         var canExtend = false
         for syllable in PinyinSyllableTable.syllables
-            where syllable.hasPrefix(prefix) && syllable.count > prefix.count
-        {
+            where syllable.hasPrefix(prefix) && syllable.count > prefix.count {
             let index = syllable.index(syllable.startIndex, offsetBy: prefix.count)
             result.insert(syllable[index])
             canExtend = true

OSGKeyboardShared/Typing/RimeResourceInstaller.swift

@@ -5,8 +5,8 @@
 // an already-built session, keeping expensive maintenance work out of
 // the extension's constrained lifecycle.
 
-import Foundation
 import Darwin
+import Foundation
 
 public enum RimeResourceError: LocalizedError {
     case appGroupUnavailable

OSGKeyboardShared/Typing/TypingSessionController.swift

@@ -4,8 +4,8 @@
 // Owns the typing-surface engine + layout provider. Injected into the
 // keyboard extension; torn down when leaving typing mode.
 
-import Foundation
 import Combine
+import Foundation
 
 @MainActor
 public final class TypingSessionController: ObservableObject {