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/overview.md

@@ -0,0 +1,52 @@
+---
+type: overview
+tags: [parking, overview, synthesis]
+sources: [parking-system-architecture]
+updated: 2026-06-14
+---
+
+# Parking System — Overview
+
+The synthesis / entry point for this wiki. Start here, then follow links. Catalog of every page:
+[[index]]. Source summaries: [[parking-system-architecture]].
+
+## What it is
+
+A **parking-management web application** running on a **dedicated, hardened Linux appliance**
+deployed on-site at a parking facility. Two forces shape nearly every decision:
+
+1. **[[offline-first]]** — a park may be air-gapped; nothing core may depend on a network.
+2. **[[threat-model]]** — the primary adversary is the **legitimate operator at the booth**, not
+   an outsider. The classic fraud is *take the cash, delete the record.*
+
+## The architecture in one pass
+
+- **Stack** ([[technology-stack]] / [[standing-decisions]]): [[turborepo]] · [[fastify]] ·
+  [[react-vite-spa]] · [[sqlite]] + [[drizzle-orm]] · [[local-jwt-auth]] — all open-licensed to
+  avoid lock-in (cf. rejected [[payload-cms]], [[refine]], [[logto-zitadel-oidc]]).
+- **Integrity** is the heart of it: an [[append-only-event-chain]] (hash-chained, [[atecc608]]-
+  signed) plus external [[reconciliation]] — *that's* what remote sync really is. Encryption at
+  rest ([[disk-os-hardening]]) defends a secondary threat.
+- **Devices** sit behind a [[device-adapter-pattern]] (swap hardware → new adapter only), with
+  the [[barrier-not-a-door]] safety principle keeping physical safety in barrier-operator firmware.
+- **Access control** hinges on the [[trust-boundary]] fork:
+  [[uhppote-vs-esp32|detection vs. prevention]]. Today: [[uhppote-controller]] behind
+  [[network-isolation]], its open [[uhppote-udp-protocol]] contained, its log made trustworthy by
+  [[event-log-ingestion]]. Upgrade path: the [[esp32-custom-controller]] with
+  [[challenge-response-auth]] and [[fail-state-safety]].
+- **Readers** split two ways ([[entry-exit-readers]]): permit holders via [[wiegand]]
+  (autonomous), casual/transient via host-side [[lpr-camera]] / QR; both can share a relay.
+- A reference [[bom]] lists recommended devices.
+
+## Where it stands
+
+6 [[open-questions]] still drive procurement — most critically **lane topology**, **failure
+modes (fail-open on exit)**, the **reconciliation channel**, and **backup/durability**.
+
+## Reading paths
+
+- *Security-first:* [[threat-model]] → [[append-only-event-chain]] → [[reconciliation]] →
+  [[uhppote-vs-esp32]].
+- *Hardware-first:* [[bom]] → [[uhppote-controller]] → [[entry-exit-readers]] →
+  [[esp32-custom-controller]].
+- *Stack-first:* [[technology-stack]] → [[offline-first]] → [[device-adapter-pattern]].