LTS-3295: add min-release-age=7 to .npmrc (clears semgrep npm-missing-minimum-release-age)

Semgrep p/default flagged `npm-missing-minimum-release-age` on this .npmrc — a
supply-chain rule (npm v11.10+) wanting a cooldown before resolving
newly-published package versions. Adding `min-release-age=7` clears it (semgrep
p/default now reports 0 findings locally). Validated inert-safe on the runner pod
via the paired Playwright prod run (pod npm treats it as harmless today; activates
as protection on npm >=11.10).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: amitsi-bs

.npmrc

@@ -19,3 +19,4 @@ audit-level=high
 legacy-peer-deps=false
 ignore-scripts=true
 engine-strict=true
+min-release-age=7