Implements the wiki design in packages/db + packages/shared.
Event split: rename events -> ledger_events (signed business ledger) and add
device_events (unsigned telemetry). ledger_events gains a signed JSON payload
(amount/tariffVersionId/sessionRef/tender…) + keyId; canonicalize() includes
the payload via sorted-key serialization so business data is tamper-evident.
Raw Dingtian input now writes device_events, not a signed input_received.
New tables: tariffs + immutable tariff_versions (composable/versioned, currency
+ FX-ready), permits (+ permit_credentials, permit_plates; maxConcurrent default
1), blocklist, sessions (rebuildable projection cache — not a source of truth).
shared: split ParkingEvent/Type into LedgerEvent/LedgerEventType + DeviceEventKind;
add LedgerPayload, Tender, TariffStructure/TariffBlock.
Regenerated a single baseline migration (no production chain data existed).
Verified: chain appends + verifyChain ok; tampering a payment payload breaks
the signature. Full repo builds (5/5).
Implement the core anti-fraud primitive: an append-only, hash-chained,
signed event log (the schema + types predated this; the writer/signer are new).
- EventLog (apps/server): serialized append, monotonic index, prevHash chain,
signature; verifyChain() detects tamper/reorder/delete. No update/delete paths.
- Signer abstraction (packages/shared) over the ATECC608 secure element, with a
SoftwareSigner (HMAC, EVENT_SIGNING_KEY) shipped now since the chip is still
open-question #6. Documented: software signer is tamper-evident but NOT
unforgeable-by-owner.
- Add ParkingEventType "input_received" for raw device inputs (not yet a
vehicle_entry, which the entry flow will append later).
- Read API: GET /api/events; integrity self-check: GET /api/events/verify (admin).
Verified on hardware: shorting the Dingtian inputs produced signed, chained
input_received events; verifyChain ok; direct DB tamper/delete detected.
NOTE: the log captures host-originated actions only. Out-of-band relay
actuation (sniffed relay_pw, string protocol, ip_watchdog) produces no event
by design -- the control is reconciliation vs. an independent witness, which is
not yet built. See wiki/concepts/append-only-event-chain.md.
julian