Phase 1: content source of truth — 40 documents across six areas

Satisfies the Phase 1 Definition of Done:

- content/ validates cleanly against the frozen schema. `make validate`
  reports OK: 40 document(s) validated, 0 violations.
- Six areas exist, each with an L1 entry: ai-overview, platform-overview,
  edge-overview, products-overview, history-overview, about-overview.
- All six areas have an L2 entry: ai-systems, platform-estate, edge-fleet,
  products-business, history-engagements, about-narrative.
- 28 L3 artefact stubs under content/<area>/l3/. Every artefacts[].url in
  every document resolves to one of them; the validator proves there are no
  dangling references (and a deliberately broken copy exits 1).
- Every metric value traces to a source line in the evidence notes or the
  approved metric set in reference/content-map.md (per-metric citations are
  recorded in the AUD-131 completion comment).
- Every document carries confidence and last_verified=2026-10-26; the
  validator rejects a missing or non-canonical value.
- docs/content-redaction.md records the redaction pass: identifiers, third
  party personal data, credentials and infrastructure detail excluded, with
  reasons, plus the two numbers that are reported rather than smoothed.

Honesty positions held: 3 businesses active (12 adoptions over time),
Where-Woof deployed and pre-market, failures kept in (edge-failures), no
promotion of in-progress work to delivered.

No site code, no templates, no CSS, no rendering (Phase 2).

content/platform/platform-overview.md

@@ -0,0 +1,25 @@
+---
+id: platform-overview
+area: platform
+level: 1
+title: "Platform & Infrastructure"
+claim: "Runs a multi-machine NixOS and Proxmox estate — fifty-plus containers · declarative configuration · encrypted backups with a written restore runbook · and public ingress — sized to the hardware rather than the budget."
+confidence: running
+period: "2020–"
+tech: [NixOS, Proxmox, Docker, Caddy, Tailscale, Borg, Kopia, AWS S3]
+metrics: [{label: "containers in the estate", value: 50}, {label: "hosts", value: 4}, {label: "backup tiers", value: "Borg · Kopia · AWS"}]
+artefacts: [{type: doc, label: "Declarative multi-host configuration", url: "content/platform/l3/platform-nixos.md"}, {type: doc, label: "Backups and restore runbook", url: "content/platform/l3/platform-backups.md"}, {type: doc, label: "A hand-written Nix package with an exit plan", url: "content/platform/l3/platform-tuios-package.md"}]
+public: true
+last_verified: 2026-10-26
+tags: [platform, devops, nixos, docker, backups]
+---
+
+# Platform & Infrastructure
+
+**Claim.** Fifty or more containers across four hosts, configuration declared rather than hand-applied, encrypted backups on three machines with a restore runbook beside them, and one public listener at the edge.
+
+**Status.** Running. Figures trace to the approved metric set and the infrastructure reference; verified 2026-10-26.
+
+**The constraint that shaped it.** The runtime host is memory-bound rather than CPU-bound. Every service in this estate carries a memory cap and is bound to loopback, which is why the platform reads as engineering under constraint instead of hardware shopping.
+
+**Start here.** [The capability page](platform-estate.md) covers what runs, where, and what was rejected.