SCANNER_PROBE_RE gap: /.flaskenv not covered (single observed hit)

2026-07-17 applog warn: /.flaskenv surfaced at warn/navigation/page_not_found instead of silent info/malicious retain. Credential-dotfile scanner probe (Flask env-file convention), same class as .env/.git/.svn - does NOT match the canonical ENVFILE regex /(^|\/)(?:[\w.~-]*\.env|env)(?:$|[./~0-9_-])/ because '.flaskenv' has no literal '.env' substring (dot precedes 'f', not 'e') and doesn't start with bare 'env'. Zero collision risk with real Pluto routes (Next.js app, no Flask). Per pluto-scanner-probe-canonical precedent (.svn re-added on first observed hit, unlike app-plausible words needing a burst), add a dedicated credential-dotfile alt e.g. (^|/)\.flaskenv(?:$|[./~0-9_-]) to SCANNER_PROBE_RE in not-found-classify.ts. Class-S, single-file regex extension.