docs: add AGENTS.md per module and unify ports to 70XX

- Add CLAUDE.md at root and AGENTS.md in apps/api, apps/indexer,
  apps/backoffice, crates/parsers with module-specific guidelines
- Unify all service ports to 70XX (no more internal/external split):
  API 7080, Indexer 7081, Backoffice 7082
- Update docker-compose.yml, Dockerfiles, config.rs defaults,
  .env.example, backoffice routes, bench.sh, smoke.sh

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

apps/indexer/Dockerfile

@@ -23,5 +23,5 @@ RUN --mount=type=cache,target=/sccache \
 FROM debian:bookworm-slim
 RUN apt-get update && apt-get install -y --no-install-recommends ca-certificates wget unrar-free && rm -rf /var/lib/apt/lists/*
 COPY --from=builder /app/target/release/indexer /usr/local/bin/indexer
-EXPOSE 8081
+EXPOSE 7081
 CMD ["/usr/local/bin/indexer"]