Session 43: Data pipeline + audit fixes + depth chart foundation (2045 tests)

P0 fixes + wiring real data into the S42 Player Intelligence architecture.

- P0 dropdown z-index: the nav's backdrop-filter stacking context let the
  Ticker/HeartbeatBar paint over the avatar/More dropdowns and eat clicks.
  nav now position:relative zIndex:2; menus zIndex:100. Avatar Settings ->
  /settings.
- Real MLB stats: mlbStatsAdapter.searchPlayer + getPlayerStats (name->id->
  season+gamelog). playerIntelService.resolvePlayerStats normalizes into the
  archetype classifier; getPlayerIntel returns found:true + real season +
  archetype classified from real stats. NBA via nbaStatsClient (degrades).
- Game cards: slateAdapter.groupPropsByPlayer (playerStrips, name once) +
  mapPitchers (MLB probables), folded into mapScheduleToGameCards. Legacy
  GameCard line grid renders BookChip (brand colors) not grey text.
- Grade card intel: analyzeViaEngine1.buildIntelFields computes stat-context +
  form/usage/matchup/rest from the existing feature vector (zero extra I/O);
  gradeAdapter lights up the card sections. Archetype deferred (needs season
  line at grade time).
- Depth chart foundation: depthChartService (getLineup/getDepthChart/
  getCascadeProjection) + /api/stats/lineup|depth|cascade, graceful + injectable.
- Mobile: player hero name overflow-wrap + 24px on <=640px (was clipping).

Backend 2011 -> 2045 tests (+34), 163 suites. Web build clean (exit 0).

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

src/routes/stats.js

@@ -3,6 +3,7 @@ const { getSupabaseServiceClient } = require('../utils/supabase');
 const { getStatFilters } = require('../config/statFilters');
 const { createRateLimit } = require('../middleware/rateLimit');
 const { getPlayerIntel, getLeaders } = require('../services/playerIntelService');
+const depthChart = require('../services/depthChartService');
 
 const router = express.Router();
 
@@ -165,4 +166,42 @@ router.get('/game/:id', intelLimit, async (req, res) => {
   }
 });
 
+// Depth chart / lineup / cascade (Session 43). Graceful — always 200 with a
+// valid (possibly empty) shape so the UI never hard-fails.
+// GET /lineup/:team?sport=mlb
+router.get('/lineup/:team', intelLimit, async (req, res) => {
+  try {
+    const sport = String(req.query.sport || 'nba').toLowerCase();
+    const lineup = await depthChart.getLineup(sport, req.params.team);
+    res.set(MISSION_HEADER).json({ sport, team: req.params.team, lineup });
+  } catch (err) {
+    console.error('[stats/lineup]', err.message);
+    res.status(503).set(MISSION_HEADER).json({ error: 'Service temporarily unavailable' });
+  }
+});
+
+// GET /depth/:team?sport=nba
+router.get('/depth/:team', intelLimit, async (req, res) => {
+  try {
+    const sport = String(req.query.sport || 'nba').toLowerCase();
+    const chart = await depthChart.getDepthChart(sport, req.params.team);
+    res.set(MISSION_HEADER).json(chart);
+  } catch (err) {
+    console.error('[stats/depth]', err.message);
+    res.status(503).set(MISSION_HEADER).json({ error: 'Service temporarily unavailable' });
+  }
+});
+
+// GET /cascade/:player?sport=nba&team=SA
+router.get('/cascade/:player', intelLimit, async (req, res) => {
+  try {
+    const sport = String(req.query.sport || 'nba').toLowerCase();
+    const cascade = await depthChart.getCascadeProjection(sport, req.params.player, req.query.team);
+    res.set(MISSION_HEADER).json({ sport, player: req.params.player, cascade });
+  } catch (err) {
+    console.error('[stats/cascade]', err.message);
+    res.status(503).set(MISSION_HEADER).json({ error: 'Service temporarily unavailable' });
+  }
+});
+
 module.exports = router;