Add the shortest runnable restart command to the docs overview and reconfirm the offline smoke

Constraint: Restrict this checkpoint to navigation and handoff documentation backed by fresh local verification
Rejected: Keep restart guidance read-only without a first command to run | New sessions benefit from an immediate executable sanity check
Confidence: high
Scope-risk: narrow
Directive: Keep README focused on compressed restart guidance and use the offline smoke only as an environment and chain sanity check
Tested: Re-ran business_export_offline_smoke.py successfully and rechecked 215 relative links across the updated docs
Not-tested: Did not connect to a live business export or run full training/evaluation beyond dry-run

+## 2026-06-02 总览页补齐最短可跑命令 checkpoint
+
+完成项：
+- 已在 `docs/README.md` 补入“新 session 最短可跑命令”。
+- 已再次重跑 `business_export_offline_smoke.py`，确认离线 smoke 仍可通过。
+
+验证结果：
+- `catalog_refs=2`
+- `train_queries=1`
+- `test_queries=1`
+- `val_queries=0`
+- `dry_run_passed=true`
+
+结论：
+- 现在新 session 不仅知道先读什么，也知道先跑什么来验证环境与链路。
+
 ## 2026-06-02 总览页一致性与最短阅读顺序 checkpoint
 
 完成项：

@@ -65,6 +65,22 @@ flowchart TD
 - 做你们自己的业务素材接入：先读 `business-export-cookbook.md`
 - 做 FMA / MTG-Jamendo 这类开放数据：先读 `open-dataset-workflow.md`
 
+## 2.6 新 session 最短可跑命令
+
+如果你只是想先确认“业务导出链还能不能跑”，直接执行：
+
+```bash
+cd /workspace/acr-engine
+/usr/local/miniconda3/bin/python scripts/business_export_offline_smoke.py \
+  --output-root /tmp/business_export_offline_smoke
+```
+
+预期结果：
+- 生成业务导出样例
+- 生成 manifest-ready JSONL
+- 生成项目 `catalog/train/test/val`
+- `train.py --dry-run` 通过
+
 ## 3. 主文档分组
 
 ### A. 项目与架构

@@ -256,6 +256,7 @@
 ### 文档入口最新状态
 - `docs/README.md` 已补齐业务数据接入导航与最短链说明。
 - `docs/README.md` 已新增“新 session 最短阅读顺序”。
+- `docs/README.md` 已新增“新 session 最短可跑命令”。
 
 ### 最优先待办
 1. 把已完成的 toy bucket baseline 升级为语义 bucket（风格 / 结构 / hard-case）。