Add network intercept/error monitor; document soak and Outline sync

- interceptNetworkCall + startNetworkErrorMonitor for page traffic
  (spy/mock + fail on silent 4xx/5xx), with unit tests
- docs/NETWORK.md, docs/IDEAS.md (OSS backlog), docs/OUTLINE.md
  (update Outline QA & Dev Playkit page on each release)
- Adoption pause: no other consumer repos until punimtag soak

docs/IDEAS.md

@@ -0,0 +1,53 @@
+# Ideas backlog (from similar OSS tools)
+
+Notes from comparing `@levkin/playkit` to public kits (2026-07). Tracking items
+also live in `ROADMAP.md` — this page expands *why* / *how*, not just the checkbox.
+
+## Already shipping (borrowed shape)
+
+- **Network interception + error monitor** — see `docs/NETWORK.md`. Sourced from
+  [`playwright-utils`](https://github.com/seontechnologies/playwright-utils)
+  (spy/stub + background 4xx/5xx “Sentry for tests”), trimmed to Levkin needs.
+
+## Documented next (not implemented yet)
+
+### Test burn-in (flake detection)
+
+`playwright-utils` “burn-in” re-runs a spec N times (local or CI) before merge.
+That is the *mechanism* behind playkit’s “flake quarantine” roadmap item —
+implement burn-in first (CLI flag or `PLAYKIT_BURN_IN=N`), then quarantine can
+consume “failed once in N” signals into Grafana / Annotations.
+
+### Scheduled synthetic monitoring
+
+[`playwright-exporter`](https://github.com/maravexa/playwright-exporter) runs
+Playwright suites on a cron and exposes pass/fail + duration as Prometheus
+metrics. Overlaps with “deploy-smoke CLI”. Prefer evaluating that tool (or a
+thin wrapper) on a schedule against punimtag DEV **before** writing a bespoke
+`playkit smoke` binary.
+
+### Functional-core / fixture-shell audit
+
+`playwright-utils` ships each utility as a plain function *and* a fixture.
+Playkit already does this for `createPlaykitRuntime`; `ApiClient` /
+`MailpitClient` are class-first. Audit later: keep classes, add thin function
+wrappers only where consumers repeatedly wrap them themselves.
+
+### Remote-write vs Pushgateway
+
+[`playwright-prometheus-remote-write-reporter`](https://github.com/vitalics/playwright-prometheus-remote-write-reporter)
+avoids a Pushgateway by writing straight into Prometheus. **Moot for now** —
+homelab Pushgateway is wired in ansible `deploy/observability` (pending apply).
+Keep as a simplification option if Pushgateway ops cost ever hurts.
+
+### Enterprise polish already on the roadmap
+
+Contract testing (OpenAPI), axe-core a11y, and visual regression match what
+`kitium-ai/playwright-helpers` treats as table stakes — already listed under
+v0.5+ in `ROADMAP.md`; no extra checklist needed.
+
+## Adoption pause
+
+**Do not wire other app repos onto playkit yet.** Shake out punimtag + kit CI
+for a few days (metrics path, release job, network helpers) before migrating
+`screening` / `slack-sieve` / `portfolio`. Revisit after that soak.