Offer Update in the project menu to move a project's runs onto the current tool code #111

A project's coordinator, designers and coder each freeze their tool code when their run is created and keep it for the run's life (#67). After the hub is rebuilt with a fix, every live run in a project keeps the old code, and the only way to move a project onto the current code is to cancel its runs by hand in the database and ask the coordinator to start them again.

Seen on 2026-11-03 on the Compose hub: after #110 landed, the project's coder still carried the package frozen on 2026-11-02 and reported "nothing under $HOME/browsers" on every check, because its frozen package had no arm64 browser entry.

Expected. The project menu (the rail row's and the top bar's) offers Update…, which replaces the project's runs that are behind the installed packages with fresh ones on the current code:

• it refuses while the coordinator is mid-turn, a delivery to it is unsettled, an approval is pending, or a specialist is mid-turn, and says which;
• a project whose runs are all current is told so and nothing changes;
• stale specialists are cancelled, and the coordinator too when it is stale; a fresh coordinator starts and the person's next message carries the held resume context to it, as the automatic upgrade already does;
• the dialog says that a coder's work not yet filed is lost and that the person should ask the coordinator to continue afterwards.

The hub already has the pieces: createCoordinatorUpgrades finds the safe point and replaces a stale coordinator with its parked specialists, but only when the coordinator's own pin is stale and never while a coder is live.