There's no license that lets people use it on a commercial website but not to sell it on a shirt.
The only way to have that situation is to keep it All Rights Reserved and make separate contracts with people for all uses. That would totally undermine your goals.
I think CC-BY-SA is what you want. People aren't likely to sell it on a shirt, and if they do, they still have to give you credit (that's the BY part), like on the shirt itself I'd think even. If you left off the -SA part, people could make new versions and make those versions restricted instead of sharing them under the same terms.
The only way to have that situation is to keep it All Rights Reserved and make separate contracts with people for all uses. That would totally undermine your goals.
I think CC-BY-SA is what you want. People aren't likely to sell it on a shirt, and if they do, they still have to give you credit (that's the BY part), like on the shirt itself I'd think even. If you left off the -SA part, people could make new versions and make those versions restricted instead of sharing them under the same terms.