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/history/l3/history-code-exhibits.md

@@ -0,0 +1,40 @@
+---
+id: history-code-exhibits
+area: history
+level: 3
+title: "Artefact — Six code exhibits across five eras"
+claim: "Six short excerpts spanning object-oriented ActionScript · a hand-written JavaScript animation engine · a PHP media pipeline · typed TypeScript · embedded C++ · and declarative Nix."
+confidence: historic
+period: "2006–2026"
+tech: [ActionScript, JavaScript, PHP, TypeScript, C++, Nix]
+metrics: [{label: "code exhibits", value: 6}, {label: "technology eras spanned", value: 5}]
+artefacts: []
+public: true
+last_verified: 2026-10-26
+tags: [history, code, exhibits, artefact]
+---
+
+# Artefact — Six code exhibits across five eras
+
+**Status: stub.** The excerpts are selected from source that exists on disk; each one lands in Phase 7 with two sentences on why it is good code.
+
+## The six
+
+| # | Era | Source | What the excerpt shows |
+|---|---|---|---|
+| 1 | Object-oriented ActionScript | the brief-case builder and the national beer campaign | class design, imports, encapsulation |
+| 2 | Hand-written JavaScript engine | the text-effects engine from the site builder (about 2 200 lines) | easing and a timeline core |
+| 3 | PHP media pipeline | the media encoder from the site builder (about 3 400 lines) | one encode operation and the FFmpeg piping around it |
+| 4 | TypeScript | the vehicle-tracking application's schema and typed service layer | types, interfaces, a router |
+| 5 | Embedded C++ | the Wi-Fi manager interface and implementation | interface versus implementation in firmware |
+| 6 | Declarative infrastructure | the 25-line Nix package definition | pinned version, verified hash, written exit condition |
+
+Total is roughly 225 lines across twenty years, which is the point: each excerpt is chosen to show judgement rather than volume.
+
+## What it proves
+
+That the stack changed six times and the discipline did not. Exhibit 6 is the least common of the six and the most current — a short, correct, self-documenting derivation with an exit plan is a stronger infrastructure signal than a long configuration file.
+
+## When it is delivered
+
+Phase 7. Source paths are recorded in the planning notes; nothing is published from a path that has not been read at capture time.