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/concepts/uhppote-udp-protocol.md

@@ -0,0 +1,38 @@
+---
+type: concept
+tags: [parking, security, access-control, protocol]
+sources: [parking-system-architecture]
+updated: 2026-06-14
+---
+
+# UHPPOTE UDP Protocol (the weakness)
+
+The [[uhppote-controller]] communicates over **UDP port 60000 with no authentication and no
+encryption**. Anyone who can place a packet on that LAN can send an "open" command to any door.
+This is *the* security issue — not safety (safety is the barrier operator's, per
+[[barrier-not-a-door]]). (See [[parking-system-architecture]] §6.)
+
+**Mitigation: [[network-isolation]] is mandatory.** The security boundary is the network because
+it cannot be the device.
+
+## Why you can't fix it in firmware
+
+The open-source `uhppoted` ecosystem is **protocol reverse-engineering only** — clients speaking
+the existing UDP protocol. No source, SDK, schematic, or toolchain to build/flash custom
+firmware. The controller accepts only the **manufacturer's official** firmware images. You
+cannot configure or patch your way to authentication on this hardware.
+
+## Unauthenticated commands that undermine the log
+
+The record-level log is append-only, but these don't touch individual records:
+
+| Vector | Command | Effect |
+| --- | --- | --- |
+| Blinding | `record-special-events false` | Stops logging door events going forward |
+| Wipe | `restore-default-parameters` | Factory reset — clears config + event state |
+| Rollover | (generate events / fall behind) | Finite circular buffer; old events overwritten |
+| Time skew | `set-time` | Corrupts / backdates timestamps |
+| Index desync | `set-event-index` | Moves the retrieval pointer; naive ingestion skips events |
+
+The defensive response is [[event-log-ingestion]]. The preventive alternative is the
+[[esp32-custom-controller]].