This is easily done by clicking the 'Show All Files' icon at the top of the server explorer; you will then see the bin folder (with a white folder icon) included in the solution explorer. You can then right click the bin folder and select 'Include In Project'.
I don't know if this is good practice however. Might be better to just use the explorer to view the files. Anyway, you could include the bin file while developing, then remove it by right clicking it and selecting 'Exclude From Project' when you are ready for the final build.