Sinny,
There are built in startup actions, and a plugin from someone else (for more functional startup actions), that can trigger any process but I think the dialogue will still appear.
What I am curious about is do you plan to load this for every user who loads the wiki, or only you responsible for publishing/saving? THis seems like a performance impact.
A Quick workaround could be to make a virtue of it and have a startup modal as if you want to refresh the data or not. You could also ties this to user ID, so when you load it and you were the last user I will only display the modal then.
I would think there may be occasions on which you would like to load the wiki and not import.
Regards
Tony