chore(insights): align the ambient-Coach file comments to the shipped version

The A1–A3 source files carried v1.22.0 docstrings from before the work was
re-cut as the v1.21.2 point release. Comment-only sweep so blame and the
in-file version tags read consistently with the shipped version.

src/app/api/insights/coach-read/route.ts

@@ -1,5 +1,5 @@
 /**
- * v1.22.0 (A1) — "Coach read" strip route.
+ * v1.21.2 (A1) — "Coach read" strip route.
  *
  * `GET /api/insights/coach-read?metric=<MeasurementType>` serves the two
  * server-authoritative lines a metric sub-page renders above its chart: the

src/app/api/insights/coach/seeded-question/__tests__/route.test.ts

@@ -2,7 +2,7 @@ import { describe, it, expect, vi, beforeEach } from "vitest";
 import { NextRequest } from "next/server";
 
 /**
- * v1.22.0 (A3) — the seeded-question route resolves today's single most
+ * v1.21.2 (A3) — the seeded-question route resolves today's single most
  * notable derived signal into a tappable Coach opener, server-side. When the
  * confidence + notability gate yields nothing the route returns
  * `{ signal: null }` and the hero keeps its neutral greeting — never a

src/app/api/insights/coach/seeded-question/route.ts

@@ -1,5 +1,5 @@
 /**
- * v1.22.0 (A3) — pre-seeded relevance opener for the unscoped Coach.
+ * v1.21.2 (A3) — pre-seeded relevance opener for the unscoped Coach.
  *
  * `GET /api/insights/coach/seeded-question` resolves today's single most
  * notable derived wellness signal (readiness / recovery shift, the same