v6.16.1 — Testing 9.5 + Documentation 9.5 (production readiness 9.7/10)

Pure test + docs release. Zero runtime code changes. Closes 2 of the 3 remaining gaps to 10/10 production readiness.

Production readiness: 9.5 → 9.7

Category	v6.16.0	v6.16.1
Testing	8.5	9.5
Documentation	9	9.5
Weighted total	9.5	~9.7

Added — 86 new tests across 4 previously-untested services

Test suite: 757/51 → 843/55.

• permissions.test.js (28 tests) — RBAC filtering: filterContainers, filterStacks, canAccessStack, canAccessContainer, grant/revoke CRUD, expired-grant cleanup. Security-critical.
• settings.test.js (17 tests) — key-value CRUD + type coercion + update audit.
• security-alerts.test.js (26 tests) — threshold + windowed rule evaluation, cooldown, event recording, top-events query.
• event-notifier.test.js (15 tests) — dispatch with mocked notificationChannels + workflows (tricky because eventNotifier dynamically require()s them inside method bodies).

Added — 3 feature reference docs in docs/features/

~3,500 words total. Every claim verified against source code.

• prometheus-metrics.md (978 words) — Complete /api/metrics reference: every metric (name, type, labels, HELP), real sample output, 4 Grafana query examples, cardinality notes.
• platform-detection.md (1,184 words) — NAS + cloud + hypervisor detection: signatures, cache behavior, how to extend, known limitations.
• translations-tooling.md (1,381 words) — v6.11.x Translations tab: architecture, admin workflow, API reference, quota math.

README gains a Feature Reference subsection linking to docs/features/.

Residual gap to 10/10 (v7-scoped)

• Docker-in-Docker integration tests — structural CI change
• Redis-backed HA mode — BACKLOG F30, 4-5 days, changes product positioning (single-instance → multi-instance)
• External 3rd-party security audit — vendor + budget

Verification

• Tests: 843 passing / 4 skipped / 55 suites.
• Lint: 0 warnings / 0 errors.
• Zero source code modifications — only src/__tests__/ and docs/ additions + README counts.