fix(daily): reset Endfield's European day on the server it's on

Endfield has two server groups, not three: Europe is served off the
Americas machine on a fixed UTC-5, so a European player's day rolls at
09:00 UTC. We were resetting it six hours early, at 03:00, which ticked
the wrong box every morning between those two instants.

Adds GameMeta.resetOffsets, a sparse per-region override, and threads an
optional `game` through every day-key function. Per region rather than
per game on purpose: a blanket offset would drag Asia — which does have
its own Endfield server — onto the Americas clock, moving day keys for
readers who never had the bug. A regression test pins Asia's output as
identical to before.

Day keys are localStorage keys, so this re-labels ticks logged between
03:00 and 09:00 UTC by European Endfield players, one day backward. No
tick is deleted and past days stay editable, but a streak can read as
broken for a day. That is the cost of correcting a wrong reset; leaving
it wrong is worse.

Co-Authored-By: Claude Opus 5 (1M context) <[email protected]>

docs/ARCHITECTURE.md

@@ -72,7 +72,7 @@ src/
   shared/
     schema.ts           zod schemas — the contract, both sides    ✓ built
     time.ts             clocks, urgency, region resets, captions  ✓ built
-    games.ts            per-game name and hue                     ✓ built
+    games.ts            per-game name, hue, and reset clock       ✓ built
     feed.ts             the /api/events.json wire contract        ✓ built
   client/                                                         ✓ all built
     main.tsx            render + service worker registration