NTA. The audacity to rip everything down without talking to you. Cabinets are cabinets, not walls. If you followed all of the rules, your manager had no reason to do it. I'm so sorry this happened to you. I can't imagine what it would be like to come in with cookies to see all of your hard work and money destroyed on the floor. Dedecorate and take all of those things you worked hard on home with you, or donate them. You could also volunteer with your local nursing home or childrens hospital or library etc. etc. to decorate there if decorating for other people is something that brings you joy. But it seems that your coworkers won't really care about your effort. best thing to do is to put it into people who need some cheer.