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/wiegand.md

@@ -0,0 +1,24 @@
+---
+type: entity
+tags: [parking, hardware, readers]
+sources: [parking-system-architecture]
+updated: 2026-06-14
+---
+
+# Wiegand
+
+The reader-wiring standard (Wiegand 26/34) used to feed reads **directly into the
+[[uhppote-controller]]'s reader port**. This is the preferred path for **permit
+holders/subscribers**, because it lets the controller **decide autonomously** from its onboard
+card list — it keeps working even if the host is down. (See [[parking-system-architecture]] §8.)
+
+- A door relay opens on **either** a valid Wiegand read on its reader port **or** a host `open`
+  command — so one lane can serve permit holders (Wiegand, autonomous) and casual/[[lpr-camera|LPR]]
+  (host command) on the same relay.
+- **Tip: check for a Wiegand output first.** Many "network" readers (e.g. Nedap/UHF) have *both*
+  a network interface and a Wiegand output. Wire the Wiegand output into the controller and you
+  keep autonomous decisioning + the native event log, sidestepping host dependency.
+- Autonomy caveat: if remote-host control is enabled, the controller expects host comms at least
+  every ~30 s or it reverts to local (onboard-card) control.
+
+Contrast with host-side identity sources in [[entry-exit-readers]].