With visa in hand, I was able to request the “Certificat de changement de résidence,” which is French for “since you’re coming to live in France, you can bring your stuff with you without paying customs duty.” The companies involved in shipping my stuff from here to there need it to get through customs.
I poked around on the French Consul in San Francisco site and found the relevant page, in French: https://sanfrancisco.consulfrance.org/spip.php?article1830. A the end of the page is a “cliquant ici” link, which is actually a mailto: with the email address my request should go to, email@example.com. I sent email with my passport, visa, and address information, and date of my move, 17 October. The nice diplomat at that address responded with a request for credit card info to charge the $24 fee. And, voila, by return email I have the certificat, a letter with an official stamp and signature.
Time elapsed since my visa appointment on 4 September: barely two weeks.