how i handle things when my buttons are pushed seems to depend a lot more on ME (am I tired, hungry, feeling sick, overwhelmed) than the actual issue (this true for anyone else???).
when i'm doing well, i recognize it as a button issue for me and deal with it quickly, decisively and calmly. for you dd's great laundry dumping scheme, if i had overheard her say that and I was doing well, then i probably would remove either her or the bin while i matter-of-factly explained that we were not going to dump that and either talk about finding a dumping alternative after mommy was done (sand, water, cooking, rag basket) or just tell her she needed to bounce in another room so mommy could finish her work. with my 4.5 yo i'm often able to reason with her enough to distract her from her bright idea verbally while finishing the job, but if i can't, then she has to be somewhere else while I finish
btw, i'm pretty protective about bins of folded laundry and keep them out of reach till i'm carrying them around to put them away to avoid mommy meltdowns, so i do understand!!
they are still too young to really appreciate what we mommies labor for them, and i have to remind myself frequently that my kiddos aren't tyring to make more work for me, they're just playing and exploring. NOT SAYING this is you, but sometimes I have a warped perspective that they are out to make trouble for me
and they are not, they are just playing or are bored and trying to do something new and fun