core: prohibit forwarding file if it's not found (#4047)

src/Simplex/Chat/Controller.hs

@@ -1121,6 +1121,7 @@ data ChatErrorType
   | CEInlineFileProhibited {fileId :: FileTransferId}
   | CEInvalidQuote
   | CEInvalidForward
+  | CEForwardNoFile
   | CEInvalidChatItemUpdate
   | CEInvalidChatItemDelete
   | CEHasCurrentCall

src/Simplex/Chat/View.hs

@@ -1968,6 +1968,7 @@ viewChatError logLevel testView = \case
     CEInlineFileProhibited _ -> ["A small file sent without acceptance - you can enable receiving such files with -f option."]
     CEInvalidQuote -> ["cannot reply to this message"]
     CEInvalidForward -> ["cannot forward this message"]
+    CEForwardNoFile -> ["cannot forward this message, file not found"]
     CEInvalidChatItemUpdate -> ["cannot update this item"]
     CEInvalidChatItemDelete -> ["cannot delete this item"]
     CEHasCurrentCall -> ["call already in progress"]