Wave 2A: real player headshots — sport-agnostic id threaded from ingestion

Threads a REAL athlete id from the snapshot's per-player stats resolve (zero
new I/O) → enriched grade → grades:{sport} → slate strip → PlayerAvatar. Real
photo where an id resolves; team-colored monogram (never a gray silhouette,
never a broken image) where it can't. Ids are never fabricated.

Ingestion (Addition 1):
- espnStatsAdapter.getSeasonAverages now RETURNS the resolved ESPN athlete id
  (was discarded) as espnId; non-numeric uid degrades to null.
- playerIntelService surfaces MLBAM playerId (MLB) / ESPN espnId (NBA/WNBA).
- snapshotService captures both per player and stores them on the enriched
  grade beside archetype/team (null when unresolved → monogram path).

Thread → component:
- slateAdapter.buildPlayerStripsFromProps carries playerId/espnId onto each
  strip; StatStrip → PlayerAvatar (accepts both ids; getHeadshotUrl routes by
  sport: MLB→mlbstatic, NBA/WNBA→a.espncdn).
- Silhouette surfaces rewired to PlayerAvatar (branded monogram on null):
  scan search dropdown (guarded MLBAM p.id) + tonight chips, SearchModal,
  HotListPanel, GradeResultCard header. Scan grade card feeds the picked
  MLBAM id through gradeAdapter.
- playerHeadshot pure URL logic extracted to CommonJS playerHeadshotUrl.js
  (unit-testable; the .ts re-exports it). nfl/nhl added to ESPN_SPORT_PATH.

Tests: tests/unit/headshotThread.test.js (per-league URL + id thread + monogram
null path) + extended snapshotService/espnStatsAdapter suites. Full suite
241 suites / 2915 green; next build exit 0.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

web/src/lib/slateAdapter.js

@@ -348,6 +348,10 @@ function buildPlayerStripsFromProps(gameProps, gradeIndex, deltaIndex, now = Dat
         player: displayName(p.player),
         team: knownTeam,
         archetype: rec && rec.archetype ? { primary: rec.archetype } : undefined,
+        // Wave 2A — real headshot id threaded from the snapshot grade
+        // (MLBAM playerId / ESPN espnId). Absent → PlayerAvatar monogram.
+        playerId: (rec && rec.playerId != null ? rec.playerId : undefined),
+        espnId: (rec && rec.espnId != null ? rec.espnId : undefined),
         lineup: lineupStatusFor(pk, knownTeam),
         injury: injuryFor(pk),
         stats: [],
@@ -359,6 +363,9 @@ function buildPlayerStripsFromProps(gameProps, gradeIndex, deltaIndex, now = Dat
       const cand = displayName(p.player);
       if (cand.length > String(byPlayer[pk].player).length) byPlayer[pk].player = cand;
       if (!byPlayer[pk].archetype && rec && rec.archetype) byPlayer[pk].archetype = { primary: rec.archetype };
+      // Fill an id from a later graded row if the first row lacked one.
+      if (byPlayer[pk].playerId == null && rec && rec.playerId != null) byPlayer[pk].playerId = rec.playerId;
+      if (byPlayer[pk].espnId == null && rec && rec.espnId != null) byPlayer[pk].espnId = rec.espnId;
     }
     if (rec) {
       const side = sideCh(rec.direction);