feat: show shortage names and explain unavailable delivery results

capabilities/am516-delivery-prediction/skills/joint-module-leadtime-report/SKILL.md

@@ -118,6 +118,22 @@ Do not use temporary curl, WebFetch, or any API method outside the controlled sc
 - Missing or unsupported models count as queried positions and remain summarized
   under `不可用候选`; do not silently skip them to pull later candidates forward.
 
+## Unavailable Result Reasons
+
+- When the original model has no usable result, stop before recording and include a separate `原因：` line. Identify missing or empty `data` / `交期汇总` objects, or each missing, empty, or invalid required workday/date field. If old lead-time fields were returned, explain that they cannot substitute for the required fields.
+- Mention missing BOM only when the response explicitly marks it as absent. Field omissions alone do not establish that a model does not exist or that materials are short.
+- Preserve a separate reason for every unavailable candidate in initial and continuation replies; do not merge them into `不存在或接口未返回交期汇总`.
+- For controlled-query failures, explain the known category: missing API Key, HTTP status and its meaning, TLS validation, DNS/connection failure, timeout, or response-format failure. Do not copy raw error messages, response bodies, secrets, or ERP details into replies.
+- If no deeper service-side cause can be confirmed, explicitly say it was not provided and needs runtime/service-log verification. Do not invent a business cause. Keep the fixed disclaimer once at the end.
+
+## Shortage Material Names Rule
+
+- For every usable model, add `缺料物料明细` using only names from `data.采购信息.缺料明细[]`. Read `物料名称`, or `缺料物料名称` when the former is absent or blank.
+- Preserve the API order, omit duplicate names, and display names separated by `；`. Include both reducer and non-reducer shortage names.
+- Do not substitute material codes, infer names from code prefixes, or list materials from the complete BOM. This added detail contains no codes, quantities, or specifications.
+- If some shortage records lack a nonblank string name, retain the available names and state how many records did not return a name. If all names are missing, state `N项缺料记录未返回物料名称，需人工复核`.
+- If the shortage list is empty, state `API未返回缺料记录`; missing shortage data or an invalid BOM retains the existing unavailable-data reminder. Do not infer that missing data means no shortage.
+
 ## Reducer Shortage Detail Rule
 
 - Treat a shortage item as a reducer only when `data.采购信息.缺料明细[].缺料物料` starts with `20.30.`.
@@ -172,6 +188,7 @@ Use this field order for a successful Feishu report:
 - 主导因素：{main factor}
 - 推荐理由：{rule-based recommendation reason}
 - 差异项：{field changes formatted as `字段 原值→新值`; join multiple changes with `；`, for example `编码器 HS→HM；品牌 DZ→LF`}
+- 缺料物料明细：{shortage material names only, separated by `；`; report missing names explicitly}
 - 减速器缺料展开：{only for shortage material codes starting with `20.30.`; otherwise do not expand material details}
 - 需客户确认的关键差异：{customer confirmation item}