Incomplete card title when a new card is saved with Cmd+Enter keyboard shortcut

> I have steps to reproduce and this bug has been reproduced by others, so opening an issue to superseded https://github.com/basecamp/fizzy/discussions/2362.

As shown in the screen recording, in a self-hosted Fizzy instance backed by a SQLite database, if the Cmd+Enter shortcut was invoked right after modifying the card title, the new title is not correctly reflected on the board view.

https://github.com/user-attachments/assets/72cf3082-6027-4899-81cc-3b4da1fe2ce5

After reloading the web page, the board view will correctly display the complete title, but it's annoying that I have to reload the page to be certain if changes have been saved.

Start by reproducing the Cmd+Enter save immediately after editing a title in a self-hosted SQLite-backed instance, then compare the behavior with discussion 2362. Trace the save and board-update entry points; done means the complete title appears on the board immediately without a page reload, with a regression test covering the case.

Written by the indexing model from the issue text.