Fix iOS chat scroll pinning

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

@@ -107,6 +107,7 @@ final class SybilViewModel {
     var isLoadingCollections = false
     var isLoadingSelection = false
     var isCreatingSearchChat = false
+    var chatBottomPinRequestID = 0
     var errorMessage: String?
 
     var composer = ""
@@ -1699,6 +1700,10 @@ final class SybilViewModel {
         isLoadingSelection = false
     }
 
+    private func requestChatBottomPin() {
+        chatBottomPinRequestID += 1
+    }
+
     private func startSelectionRefreshTask() -> Task<Void, Never> {
         isLoadingSelection = true
         let task = Task { [weak self] in
@@ -1752,6 +1757,7 @@ final class SybilViewModel {
                     }
                     selectedChat = chat
                     selectedSearch = nil
+                    requestChatBottomPin()
 
                     if let provider = chat.lastUsedProvider,
                        let model = chat.lastUsedModel,
@@ -1824,6 +1830,7 @@ final class SybilViewModel {
         } else {
             pendingDraftChatState = PendingChatState(chatID: nil, messages: optimisticMessages)
         }
+        requestChatBottomPin()
 
         if chatID == nil {
             let created = try await client.createChat(title: nil)
@@ -1871,6 +1878,7 @@ final class SybilViewModel {
         if let draftPending = pendingDraftChatState {
             pendingDraftChatState = nil
             pendingChatStates[chatID] = PendingChatState(chatID: chatID, messages: draftPending.messages)
+            requestChatBottomPin()
         } else if pendingChatStates[chatID] == nil {
             pendingChatStates[chatID] = PendingChatState(chatID: chatID, messages: optimisticMessages)
         } else {