feat: adopt new backend api for attachment (#13336)

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->

## Summary by CodeRabbit

* **New Features**
* Introduced a new query for applying document updates using AI,
allowing merged markdown responses.
* Added support for an optional file upload field when creating chat
messages.

* **Improvements**
* Enhanced recent Copilot sessions query with pagination by adding an
offset parameter.
* Refined attachment handling in chat responses to better distinguish
between single and multiple file uploads, improving reliability.

* **Bug Fixes**
  * Minor update to error handling for clearer messaging.

* **Chores**
* Cleaned up and updated iOS project configuration files for improved
build consistency.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

packages/frontend/apps/ios/App/App.xcodeproj/project.pbxproj

@@ -3,7 +3,7 @@
 	archiveVersion = 1;
 	classes = {
 	};
-	objectVersion = 77;
+	objectVersion = 56;
 	objects = {
 
 /* Begin PBXBuildFile section */
@@ -90,6 +90,8 @@
 /* Begin PBXFileSystemSynchronizedRootGroup section */
 		C45499AB2D140B5000E21978 /* NBStore */ = {
 			isa = PBXFileSystemSynchronizedRootGroup;
+			exceptions = (
+			);
 			path = NBStore;
 			sourceTree = "<group>";
 		};
@@ -337,13 +339,9 @@
 			);
 			inputFileListPaths = (
 			);
-			inputPaths = (
-			);
 			name = "[CP] Embed Pods Frameworks";
 			outputFileListPaths = (
 			);
-			outputPaths = (
-			);
 			runOnlyForDeploymentPostprocessing = 0;
 			shellPath = /bin/sh;
 			shellScript = "\"${PODS_ROOT}/Target Support Files/Pods-AFFiNE/Pods-AFFiNE-frameworks.sh\"\n";