Thirty-four days before the disgraced Theranos founder Elizabeth Holmes was due in federal prison to serve an 11-year sentence for conspiracy and fraud, she and her partner, Billy Evans, welcomed a film crew into their beachside cottage. The idea, Holmes and Evans said, was to help the public understand who Holmes really is. The narrative was incorrect. The journalists and the television shows, like the Hulu miniseries “The Dropout,” had gotten her wrong. And so, in one of the many mysteries of this fascinating project, they chose Nathan Fielder, a comedian known for blurring fiction and reality in absurdist shows like “Nathan for You” and “The Rehearsal,” to come into their rented home in Del Mar, California, and document their life with their two young children in her final days before prison. They even invited Fielder to stay with them — an offer that he declines at first but later accepts, about 20 days in. The resulting film, “You Can See Everything,” (in theaters Friday) defies categorization. In some ways, it is a staggering piece …