Get credit usage history

Returns credit-consuming activity for the team's organization, newest first - what each charge was for, when, which brand, and how many credits. Filter with q, teams, categories (snowy | ai-visibility | content) and creditMin/creditMax. Returns one page plus a nextCursor; pass it back as cursor to keep reading, and keep going before concluding a total. Use for questions like 'what did I spend credits on' or 'why did my balance drop'.