Add track layout tracking so lap-time stats stay comparable

Clubs that reconfigure their track (e.g. running indoors in the same
building) can now add named track layouts under Settings, each with
just a start date/time - layouts are contiguous, so a layout's end is
implicitly the next one's start, with no separate field to keep in
sync. Every session freezes which layout was active when it started,
so the "track record" audio cue and the Results Archive (which now
shows each session's layout) only compare laps run on the same
physical track. With no layouts configured, everything behaves
exactly as before - the feature is fully inert until a club uses it.

Design settled through conversation with the user: global scope (not
per class), start-date-only (no redundant stop date), and no changes
needed to driver/transponder mapping, since that's already fully
independent of track geometry in this app.

Deliberately out of scope for this pass: the mobile/driver training
profile's own cross-session personal-best trend stats still compare
across a driver's whole lap ledger regardless of layout - logged in
ROADMAP.md as a real remaining gap for a later pass.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

CHANGELOG.md

@@ -8,6 +8,12 @@ The application version is maintained in `package.json` and displayed in the adm
 
 No changes recorded yet.
 
+## 1.9.0 - 2026-09-10
+
+### Added
+
+- Clubs that reconfigure their track layout (common when running indoors in the same building) can now add track layouts under Settings, each with a name and a start date/time. Every session is tagged with whichever layout was active when it started, so the "track record" audio cue and the Results Archive (which now shows each session's layout) only compare lap times run on the same physical track. With no layouts added, everything behaves exactly as before.
+
 ## 1.8.0 - 2026-09-09
 
 ### Added