cx-sstream-in-loop — removed 2026-10-23 (Asia/Shanghai)

这篇还没有中文，下面是英文原文。

Status: removed. At -O2, building an ostringstream every iteration versus clearing one stream was 1.24× (100000 ops, two small insertions). The earlier 1.80× figure was the same shape and still small.

• Slug never reused.
• Historical JSONL and markdown stay beside this note. Fixtures moved under _removed/fixtures/.
• Gate: a fair microbench that stays near 1× cannot remain an active lint.