feat: add server-side ETL pipeline, revert client to NocoDB reads

ETL Pipeline (server):
- POST /api/etl/sync?mode=full|incremental — fetches ERP, aggregates, writes NocoDB
- nocodbClient.ts: table discovery, paginated delete/insert
- etlSync.ts: orchestrates fetch → aggregate → upsert
- museumMapping.ts moved from client to server
- Auth via ETL_SECRET bearer token

Client:
- dataService.ts reverts to reading NocoDB DailySales table
- Paginated fetch via fetchNocoDBTable (handles >1000 rows)
- Suspicious data check: prefers cache if NocoDB returns <10 rows
- Deleted erpService.ts and client-side museumMapping.ts

First full sync: 391K transactions → 5,760 daily records in 108s.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

start-dev.sh

@@ -0,0 +1,45 @@
+#!/usr/bin/env bash
+# Temporary dev script for ERP migration — starts NocoDB + Express server + Vite
+
+set -e
+
+cleanup() {
+  echo ""
+  echo "Shutting down..."
+  kill $SERVER_PID $CLIENT_PID 2>/dev/null
+  docker stop nocodb 2>/dev/null
+  echo "Done."
+}
+
+trap cleanup EXIT INT TERM
+
+cd "$(dirname "$0")"
+
+# Start NocoDB
+if docker ps --format '{{.Names}}' | grep -q '^nocodb$'; then
+  echo "NocoDB already running on port 8090"
+else
+  echo "Starting NocoDB..."
+  docker start nocodb 2>/dev/null || docker run -d \
+    --name nocodb -p 8090:8080 nocodb/nocodb:latest
+fi
+
+echo "Waiting for NocoDB..."
+for i in $(seq 1 30); do
+  curl -s http://localhost:8090/api/v1/health >/dev/null 2>&1 && echo "NocoDB ready" && break
+  sleep 1
+done
+
+# Start Express server (port 3002)
+echo "Starting Express server..."
+(cd server && npm run dev) &
+SERVER_PID=$!
+
+sleep 2
+
+# Start Vite (port 3000)
+echo "Starting Vite..."
+npx vite &
+CLIENT_PID=$!
+
+wait $CLIENT_PID