After premiering “Aquarela” in Berlin, renowned Russian director Victor Kossakovsky — whose titles also include “Gunda” and “Architecton” — immediately received an email. “You understand me. I need to show you something,” said the mailer, and against his usual practice of deleting fan messages, the filmmaker agreed to meet for a coffee the next day. The “unbelievable” sight of what was inside the woman’s house-slash-office would come to inspire his latest film, “Trillion,” world premiering at