docs: fix the partitioning conflict the review caught

Postgres requires a partitioned table's unique constraints to cover the
partition key, so ranging on created_at forces the primary key to
(call_id, created_at) -- and ON CONFLICT (call_id) DO NOTHING then
matches no constraint at all. The retention design claimed INSERT stays
transparent under partitioning; that holds for the routing, not for the
conflict target, and telemetry would have failed outright on any
partitioned deployment. The write drops its conflict target, which is
byte-equivalent on a plain table and legal on both.

The cap design gains the three emitter construction sites it has to
touch and the relationship to the 200-char caps embed and OCR already
carry: they stay, and the new cap is the stricter of the two. Covering
all three call paths is deliberate -- their rows land in one table, and
issue #11 settled that argument already.

research-wiki/designs/issue12-telemetry-retention.md

@@ -20,3 +20,4 @@ date: 2026-08-19
 - **文档必须进 README 而非 wiki**: sdist 只打包 `src/` 与 README(无 MANIFEST.in),wiki 里的模板下游 `pip install` 后读不到——56f3805 的教训。README 的模板 SQL 另设真实 PG 集成测试逐条执行,因为下游照抄错 SQL 就中招。
 - **被否决备选**: 缺省即截断(所有现有下游遥测正文被静默削短);库内建 TTL/清理(库需 DELETE 权限,与 (c) 的 REVOKE 建议直接冲突,且"纯 asyncio 中立、无全局状态"铁律排斥库内定时任务);给 `TelemetryRecorder` 加 `purge_before(ts)`(冻结签名的端口扩展 + 同样的权限冲突);只写文档不改代码(下游唯一手段是不用遥测)。
 - **共同边界(建议入 ARCHITECTURE D15)**: 库对下游库只做 SELECT/INSERT(加可选建表),一切改结构与删数据的操作交给下游,库的义务是把需要执行的 SQL 明明白白告诉下游。本设计与 [[design:issue13-schema-mode]] 各实现它的一面。
+- **审查留痕(Codex,2026-08-19)**: 报 3 项,**采纳 1 项、部分采纳 1 项、不采纳 1 项**。① 阻断级的分区表与幂等冲突已采纳,修法归 [[design:issue13-schema-mode]] §4.6,本设计 §6.1 承接分区部署下的语义差异(缓存命中行复用历史 `call_id`,分区表上不再被幂等吞掉)。② `text_cap` 漏列 emitter 构造点——缺口成立(`client.py:149`/`embedding.py:131`/`ocr.py:130` 三处不改即 `TypeError`),已补;但其"覆盖 embed/OCR 属语义扩散"的价值判断**不采纳**: 三条链路的行落同一张表,只覆盖一条会让同表内一半受控一半不受控(issue #11 同款判断),且核实后 embed 与 OCR 各已有 200 字符自有上限,新 cap 与之是"取更严者",实际影响远小于顾虑。③ "缺省不截断只解决一半"是人类已定的 E-a 决策而非疏漏,不改;作为补偿,README 须给一段可直接照抄的**合规下游推荐配置**(cap + 分区 retention + 三角色),不把三件事散着让下游自己拼。