Initial scaffold: Turborepo monorepo + design wiki

Turborepo (pnpm workspaces) with all dependencies pinned to latest
mutually-compatible versions: turbo 2.9, TypeScript 6, Fastify 5,
React 19, Vite 8, better-sqlite3 12 + Drizzle ORM 0.45.

Layout:
- apps/server   Fastify backend (local JWT auth + role guard, /health)
- apps/web      React 19 + Vite 8 operator SPA
- packages/db   Drizzle schema on SQLite/WAL; append-only events + users
- packages/devices  reader/printer/relay adapter interfaces (intent-only relay)
- packages/shared   shared domain types

Architecture constraints from the design wiki are encoded in the scaffold:
append-only hash-chained + signed event log, device-agnostic adapters,
"a barrier is not a door" (relay expresses intent only), fully-local
offline-first auth.

wiki/ is an LLM-maintained Obsidian knowledge base (28 pages) ingested
from the architecture & design notes, with its own maintenance schema.

Verified: pnpm install, full turbo build (5/5), server boots and serves
/health, drizzle-kit generates the initial migration.

wiki/entities/atecc608.md

@@ -0,0 +1,24 @@
+---
+type: entity
+tags: [parking, hardware, security, crypto]
+sources: [parking-system-architecture]
+updated: 2026-06-14
+---
+
+# ATECC608 (secure element)
+
+An inexpensive **secure element** holding a signing key that **cannot be extracted, even by
+someone who owns the machine**. The keystone of integrity in this system. (See
+[[parking-system-architecture]] §3, §7.)
+
+Two distinct uses:
+
+1. **Host-side event signing.** Each event in the [[append-only-event-chain]] is signed by the
+   ATECC608 on the host machine. This is what makes the hash chain **unforgeable** rather than
+   merely self-consistent.
+2. **Custom controller command authentication.** On the [[esp32-custom-controller]], it holds
+   the key(s) for [[challenge-response-auth]] — generated on-chip, non-extractable, so popping
+   the cabinet and dumping flash yields nothing usable.
+
+Confirming ATECC608 wiring/usage on both ends is [[open-questions]] #6. Listed in the [[bom]]
+on the host machine.