Use the ClientFactory pattern everywhere replacing raw ClientBuilders.

# Conflicts:
#	ElementX/Sources/Services/UserSession/UserSessionStore.swift
#	NSE/Sources/NSEUserSession.swift

ElementX/Sources/Services/Client/ClientFactoryProtocol.swift

@@ -0,0 +1,40 @@
+//
+// Copyright 2026 Element Creations Ltd.
+//
+// SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+// Please see LICENSE files in the repository root for full details.
+//
+
+import MatrixRustSDK
+
+// sourcery: AutoMockable
+nonisolated protocol ClientFactoryProtocol {
+    // MARK: Authentication
+    
+    #if IS_MAIN_APP
+    func makeAuthenticationClient(homeserverAddress: String,
+                                  sessionDirectories: SessionDirectories,
+                                  passphrase: String,
+                                  clientSessionDelegate: ClientSessionDelegate,
+                                  appSettings: AppSettings,
+                                  appHooks: AppHooks) async throws -> ClientProtocol
+    
+    func makeInMemoryClient(homeserverAddress: String,
+                            clientSessionDelegate: ClientSessionDelegate,
+                            appSettings: AppSettings,
+                            appHooks: AppHooks) async throws -> ClientProtocol
+    
+    // MARK: Restoration
+    
+    func makeAppClient(credentials: KeychainCredentials,
+                       clientSessionDelegate: ClientSessionDelegate,
+                       appSettings: AppSettings,
+                       appHooks: AppHooks) async throws -> ClientProtocol
+    #endif
+    
+    func makeNSEClient(credentials: KeychainCredentials,
+                       roomID: String,
+                       clientSessionDelegate: ClientSessionDelegate,
+                       appSettings: CommonSettingsProtocol,
+                       appHooks: AppHooks) async throws -> ClientProtocol
+}