/design seed: integration + captured-audio CI gates (nightly and release)

[genwave-radio]

/design seed from the 2026-09-10 repository review (R08). Ruling 2026-09-15: becomes an epic, sequenced after gh-#649.

Problem. .github/workflows/ci.yml:49 runs --filter "Category!=Integration"; the real-Postgres migration probes (Story346) and the Kokoro/engine fixtures never run in CI. tools/smoke_test.sh and tools/onair_gate.sh are manual. Architecture tests pin SQL text and statement order, which proves conventions, not executable migrations or role grants. A green PR run says nothing about a migration that only breaks on a real database or an audible fallback.

Proposed shape (for /design, not decided).

• A scheduled (nightly) job: Category=Integration on a clean runner with unique compose projects, cleanup on failed init, artifacts retained (logs, schema version, trx).
• A release-gate job: fresh install + upgrade-from-previous-tag migration against real Postgres; captured-audio gate measuring gaps, not HTTP 200.
• Audit the 102 skipped tests into: manual acceptance spec, obsolete, automation candidate.

Acceptance (epic-level).

• Fresh and upgrade migrations execute against real Postgres in CI, including the role boundary.
• API-down, DB-down, engine-reconnect and return-from-safe have cross-process coverage.
• Release notes state what ran, what was skipped, and what needs manual evidence.

Blocked by: gh-#649 (address-pool exhaustion), gh-#710 (temp-dir leak), gh-#723 (wall-clock flake).

[genwave-radio]

✅ Shipped in v5.9.0 — the first release its own gate proved. Release run: https://github.com/GenWave-Org/genwave/actions/runs/35219533645 (build-test → build-images → merge-manifests → stack-gate → promote → create-release, all green). The Release (https://github.com/GenWave-Org/genwave/releases/tag/v5.9.0) carries the proof: fresh install healthy and on air, upgrade from v5.8.3 with the role boundary ok, 360 s capture at −17.1 LUFS against −16, zero silence events, 16 booth_log rows. Demo pulled v5.9.0 on 2026-09-17 12:42Z; Loki listening check clean. Follow-ups: gh-#796 (nightly tier 2 red), gh-#794 (silence-count flake), gh-#804 (report readability).