Fix the ROOT: bind props to their real game, never date by the grade clock

Order 1.5 Phase 1. PropLine emits NO commence_time (grep-verified: zero
hits in proplineAdapter), so ledgerService's
`dateET(prop.game_time) || dateET(gradedTs)` always fell through to the
GRADE timestamp — and a 01:00/03:00 UTC snapshot is 21:00/23:00 ET the
PREVIOUS day. Tonight's props were filed under yesterday, settlement
correctly found no game there, and Order 1's void logic turned that into
64 destroyed results.

gameBinder.attachGameTimes() now matches every prop to a scheduled game by
TEAMS across the plausible ET window (grade date, +1, -1) and attaches the
GAME'S OWN time/date/id. It runs in snapshotService before grading and
before the ledger write, so ledger, retention and settlement all inherit
the correct date from one place.

HARD CONTRACT: an unbindable prop returns NOTHING. ledgerService no longer
has a grade-clock fallback — a row with no real game time is SKIPPED and
counted, because a mis-dated row is fabricated data and the ledger holds
real values or nothing. A slate that binds nothing pages.

DOUBLEHEADERS are reported, never guessed: two games with the same teams
on one date mark the binding `ambiguous` so settlement can decline rather
than attribute a prop to the wrong game. (Real example already in the
data: mlb:2026-07-11:MilwaukeeBrewers@PittsburghPirates(Game1).)

Also fixes retention, which had the SAME bug from last night — I had
dated model_snapshots rows with the snapshot clock. Rows now take the ET
date of the bound game_time.

Suite 282/3381 green, build exit 0.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01SmNjJAwEnqHPtXbvSZR8kA

src/services/retentionService.js

@@ -28,6 +28,16 @@
 const crypto = require('crypto');
 const { normalizeName, nameKey } = require('../utils/playerName');
 
+/** ET calendar date of an ISO timestamp (shares gameBinder's rule). */
+function etDateOf(iso) {
+  if (!iso) return null;
+  const t = new Date(iso);
+  if (Number.isNaN(t.getTime())) return null;
+  return new Intl.DateTimeFormat('en-CA', {
+    timeZone: 'America/New_York', year: 'numeric', month: '2-digit', day: '2-digit',
+  }).format(t);
+}
+
 /**
  * Bump when the grading model changes in a way that makes rows non-comparable.
  * This is the marker `ledger_entries` never had.
@@ -82,7 +92,10 @@ function rowsFromSides(base, sides, ctx = {}) {
 
       sport: ctx.sport,
       game_id: ctx.gameIdFor ? ctx.gameIdFor(base, s) : (base.game_id || `${ctx.sport}:${ctx.gameDate}`),
-      game_date: ctx.gameDate,
+      // Session 64 (Order 1.5) — the GAME's date, from the bound game_time,
+      // never the snapshot clock. ctx.gameDate is only a last resort for props
+      // the binder could not tie to a real game.
+      game_date: etDateOf(base && base.game_time) || ctx.gameDate,
       player_key: nameKey(player),
       player_name: normalizeName(player).display || player,
       team: s.team || base.team || null,