feat: dealer flow, mirror portfolio (M21), options convexity, FINRA short interest, alert producers, vendor gate

Snapshot of in-progress module work across multiple slices:

- Dealer Flow: dealerExposureEngine, dealerMapService, dealerMapExplain,
  dealerMapIntegrity, dealerMapReplay, dealerStudyEngine, hanStyleLevels
- Mirror Portfolio (M21): fundRepository, captureIngest, mirrorAlertProducers,
  fund holdings strip, live book, position capture ingest
- Options: BSM, NormalizedOptionSurface types, OptionsChainRouter,
  ConvexityGate, option legs panel
- Alert producers: vixLevel, rotation, thesis, unlock, portfolioRisk,
  mirror (fund_capture, fund_13f, mirror_diff)
- FINRA short interest adapter + queue integration
- SEC company tickers adapter + ingest (symbol search index seed)
- Vendor gate (rate-limit-first data plane, ADR-0009)
- CUSIP registry, reverse 13F refresh, stock float service
- LRU cache, portfolio backtest engine
- Frontend: dealer-flow, funds, journal, lab, monitor, plan, portfolio,
  reports, screener, strategies, theses, guided-start, exits, more pages
- Volume profile, workspace profile, visibility-aware poll
- ADRs 0010 (mirror math not advice), 0011 (symbol search index)
- VENDOR_INTEGRATIONS.md, END_USER_TEST.md
- .gitignore: exclude DBs, .DS_Store, local config, agent scratch

app/next.config.ts

@@ -1,7 +1,8 @@
 import type { NextConfig } from "next";
 
-// Proxy /api/* to the local Bun/Node backend (slice 1f) so the SPA and backend share an
-// origin — session cookies work without cross-origin/CORS gymnastics (DESIGN.md §2.1).
+// /api/* is handled by app/api/[...path]/route.ts (long-timeout proxy to :3001).
+// Do NOT use rewrites for /api - Next rewrite proxy hard-times-out ~30s and returns
+// plain "Internal Server Error" for slow LLM paths (dealerMap.explain, userLlm.test).
 const nextConfig: NextConfig = {
   typescript: {
     // The server/ directory uses .ts import extensions (Node native TS) and has its
@@ -9,9 +10,6 @@ const nextConfig: NextConfig = {
     // to avoid false errors from server files that aren't part of the frontend bundle.
     ignoreBuildErrors: true,
   },
-  rewrites: async () => [
-    { source: "/api/:path*", destination: "http://localhost:3001/api/:path*" },
-  ],
 };
 
 export default nextConfig;