There is a way to automatically clean up formatting in pasted text. Click the Past as Plain Text button, and anything you paste into the box will have the formatting removed.
Also, you can set the Paste as Plain Text to be the default setting in the editor in the Account Settings page (Options menu). That's how I personally have it set, so I never need to worry about pasting miscellaneous styles from wherever I am pasting from.
If you are looking for a feature that would take a random table from some other source or website and then transform it into a perfectly-designed table within the Lottery Post forums, I'm afraid that such a tool does not exist anywhere. Even high-end software like Excel struggles with that. It's just beyond the scope of what a website forum can handle. Your best bet is to either paste it as plain text and then re-format, or else paste in Excel, clean it up in there, and then paste from Excel into Lottery Post. (Lottery Post does handle Excel pasting pretty well.)
If you have a table full of Pick 3 numbers that you just want to clean up into a list of numbers without any formatting at all, there is actually a cool way to do that in LP, using Deflate or Inspector.
Just paste the table of numbers into the input box of Deflate or Inspector, then Deflate/Inspect the numbers, and you will see in the output it shows you the raw list of numbers you just Deflated/Inspected. You can copy that list and paste elsewhere.