adds the ability to rename chats

ios/Packages/Sybil/Sources/Sybil/SybilViewModel.swift

@@ -851,6 +851,40 @@ final class SybilViewModel {
         }
     }
 
+    func renameChat(chatID: String, title: String) async {
+        guard isAuthenticated else {
+            return
+        }
+
+        let trimmedTitle = title.trimmingCharacters(in: .whitespacesAndNewlines)
+        guard !trimmedTitle.isEmpty else {
+            errorMessage = "Enter a chat title."
+            return
+        }
+
+        SybilLog.info(SybilLog.ui, "Renaming chat \(chatID)")
+        errorMessage = nil
+
+        do {
+            let updated = try await client().updateChatTitle(chatID: chatID, title: trimmedTitle)
+            chats.removeAll(where: { $0.id == updated.id })
+            chats.insert(updated, at: 0)
+            upsertWorkspaceChat(updated)
+
+            if selectedChat?.id == updated.id {
+                selectedChat?.title = updated.title
+                selectedChat?.updatedAt = updated.updatedAt
+                selectedChat?.initiatedProvider = updated.initiatedProvider
+                selectedChat?.initiatedModel = updated.initiatedModel
+                selectedChat?.lastUsedProvider = updated.lastUsedProvider
+                selectedChat?.lastUsedModel = updated.lastUsedModel
+            }
+        } catch {
+            errorMessage = normalizeAPIError(error)
+            SybilLog.error(SybilLog.ui, "Rename failed", error: error)
+        }
+    }
+
     func refreshAfterSettingsChange() async {
         SybilLog.info(SybilLog.ui, "Settings changed, reconnecting")
         settings.persist()