feat(nginx): add /rag-originals/ location for QA PDF serving

Serves original regulation PDFs from ~/rag-originals/ on port 3002
for the RAG QA Split-View Chunk-Browser. Adds volume mount to nginx.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

docker-compose.yml

@@ -76,6 +76,7 @@ services:
       - ./nginx/conf.d:/etc/nginx/conf.d:ro
       - vault_certs:/etc/nginx/certs:ro
       - ./nginx/html:/usr/share/nginx/html/portal:ro
+      - /Users/benjaminadmin/rag-originals:/data/rag-originals:ro
     depends_on:
       vault-agent:
         condition: service_started