Products And Orders Pages Fast Again On Large Accounts

A round of backend work on the Products and Orders list pages and the order detail page. On large accounts these pages had been creeping up to tens of seconds, and on the largest order histories the Orders list was timing out entirely and falling through to an empty state. They're all back down to milliseconds, regardless of how many products or orders an account has.

Order detail pages also return immediately again — the activity timeline fills in once the main page is up, instead of holding the whole page back until it's ready.