App 2.12.1: no scroll bars; energy since start

The pages' scroll bars never faded on the car: a ScrollView shows its
bar on every layout, and the live values lay the page out every two
seconds. StableScrollView, the root of every page, now has none.

A new "Energy since start" tile, left of "Usage since start", shows the
net kWh taken from the pack since the trip began, recuperation counted
back.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01QLJfZQZeAKAwSqViTmLzki

SPECS.md

@@ -113,6 +113,9 @@ tyre pressures, GPS (lat, lon, elevation, heading) and the is_* flags. It does *
   INGEST_TOKEN) into git and pushed it. Commit amended and force-pushed; both values regenerated in
   the now gitignored `k8s/secrets.yaml` (since moved to `k8s/secrets/secrets.yaml`, outside
   `kubectl apply -f k8s/`). Filled-in secrets live only there from now on.
+- 2026-10-18 — App 2.12.1: no scroll bars (the 2-second refresh kept them from ever fading);
+  "Energy since start" tile (net kWh of the trip, recuperation counted back) left of "Usage since
+  start".
 - 2026-10-18 — App 2.12.0, server 2.5.0: settings entered on a phone. "Enter on phone" shows a QR
   code; the phone form on the server (approval password) takes the ABRP credentials, charging
   price and usable capacity, and the car collects them once (RFC 8628-style, like pairing; values