docs(wiki): the pages the 4.3.1 changes left behind

The check-in is an anchor now, not an earliest arrival, and a booked night
leads its check-in day, which the road trip and accommodation pages said
otherwise. Upgrading gains a 4.3.1 section for the reseat migration and for
what better-sqlite3 13 asks of a source install. The collaboration page knows
that links are chips and editable, the audit log knows the new admin action
and the SSO register row, and the MCP pages know the provider parameter and
the Google-only switch.

wiki/Updating.md

@@ -97,6 +97,13 @@ A few defaults change with 4.3.0. None of them needs a manual step, but they are
 - **Booked nights get a stop.** A migration puts every existing stay that has a place on its check-in day as a hotel stop, so the trips you already have show their hotels in the [Road-Trip](Road-Trip) view without anyone re-saving a booking. Under **Days** nothing changes: that stop stays hidden behind the badge the booking already shows. See [Accommodations](Accommodations).
 - **Two things are on by default.** The **Links** tab in Collab, which an admin switches off under **Admin → Addons**, and the routing counters, daily totals of the route requests the planner makes that never leave the instance. An admin reads them at `/api/route-usage/summary`; an `app_settings` row named `route_usage_enabled` with the value `false` switches them off.
 
+## Upgrading to 4.3.1
+
+Two things change with 4.3.1. Neither needs a manual step on Docker, but they are worth knowing before you pull the image:
+
+- **Booked nights lead their day.** A migration moves every booked night to the head of its check-in day, behind only a stop whose own time is at or before the check-in, and the stops without an hour follow it: a hotel booked for ten in the morning is reached at ten in the [Road-Trip](Road-Trip) view, not at a quarter past twelve behind a whole day of untimed stops. A night booked for the end of a driving day heads that day too when its stops carry no time of their own, so such a day now reads hotel first. A via point drawn on the road into that hotel from the stop that is now last is removed, because that leg no longer exists in the day, the same way a drag would remove it; the other vias follow their stops. Under **Days** nothing changes. To put a hotel back at the end, drag it down the day in the Road Trip rail, or give the first stop after it a start time at or before the check-in, which brings the untimed stops behind that one along; a time on the last stop alone leaves the hotel in the middle of the day. See [Accommodations](Accommodations#on-the-route).
+- **Source installs need a build toolchain, or `--ignore-scripts`.** The server runs better-sqlite3 13, which ships its binaries inside the package, so nothing is compiled any more; the Docker image and the Helm chart are unaffected. On an install that runs `npm ci` itself, outside Docker, a lockfile-driven `npm ci` still runs node-gyp against those binaries and stops without Python 3 and a C++ toolchain (`build-essential` on Debian/Ubuntu, the Xcode Command Line Tools on macOS, the Visual Studio Build Tools on Windows; npm/cli#9837). Either keep those installed, as [Development-environment](Development-environment) lists them, or run `npm ci --ignore-scripts`, which is what the image does.
+
 ## Encryption Key Note
 
 If you are upgrading from a version that predates the dedicated `ENCRYPTION_KEY` (i.e. you have no `ENCRYPTION_KEY` environment variable set), TREK automatically falls back to `./data/.jwt_secret` on startup and immediately promotes it to `./data/.encryption_key`. No manual steps are required — the transition is handled at first boot after the upgrade.