docs consolidation

docs/notifications/architecture.md

@@ -19,10 +19,10 @@ Tenant API│  REST + gRPC WIP │        │ rules/channels│
           └───────▲──────────┘        │ deliveries    │
                   │                   │ digests       │
    Internal bus   │                   └───────────────┘
- (NATS/Redis/etc) │
+ (NATS/Valkey/etc)│
                   │
         ┌─────────▼─────────┐      ┌───────────────┐
-        │ Notify.Worker     │◀────▶│ Redis / Cache │
+        │ Notify.Worker     │◀────▶│ Valkey / Cache│
         │ rule eval + render│      │ throttles/locks│
         └─────────▲─────────┘      └───────▲───────┘
                   │                        │
@@ -38,13 +38,13 @@ Tenant API│  REST + gRPC WIP │        │ rules/channels│
 - **Worker** subscribes to the platform event bus, evaluates rules per tenant, applies throttles/digests, renders payloads, writes ledger entries, and invokes connectors.
 - **Plug-ins** live under `plugins/notify/` and are loaded deterministically at service start (`orderedPlugins` list). Each implements connector contracts and optional health/test-preview providers.
 
-Both services share options via `notify.yaml` (see `etc/notify.yaml.sample`). For dev/test scenarios, an in-memory repository exists but production requires PostgreSQL + Redis/NATS for durability and coordination.
+Both services share options via `notify.yaml` (see `etc/notify.yaml.sample`). For dev/test scenarios, an in-memory repository exists but production requires PostgreSQL + Valkey/NATS for durability and coordination.
 
 ---
 
 ## 2. Event ingestion and rule evaluation
 
-1. **Subscription.** Workers attach to the internal bus (Redis Streams or NATS JetStream). Each partition key is `tenantId|scope.digest|event.kind` to preserve order for a given artefact.
+1. **Subscription.** Workers attach to the internal bus (Valkey Streams or NATS JetStream). Each partition key is `tenantId|scope.digest|event.kind` to preserve order for a given artefact.
 2. **Normalisation.** Incoming events are hydrated into `NotifyEvent` envelopes. Payload JSON is normalised (sorted object keys) to preserve determinism and enable hashing.
 3. **Rule snapshot.** Per-tenant rule sets are cached in memory. PostgreSQL LISTEN/NOTIFY triggers snapshot refreshes without restart.
 4. **Match pipeline.**
@@ -85,7 +85,7 @@ Failures during evaluation are logged with correlation IDs and surfaced through
 | `templates` | Locale-specific render bodies. | `id`, `tenant_id`, `channel_type`, `key`; index on `(tenant_id, channel_type, key)`. |
 | `deliveries` | Ledger of rendered notifications. | `id`, `tenant_id`, `sent_at`; compound index on `(tenant_id, sent_at DESC)` for history queries. |
 | `digests` | Open digest windows per action. | `id` (`tenant_id:action_key:window`), `status`; index on `(tenant_id, action_key)`. |
-| `throttles` | Short-lived throttle tokens (PostgreSQL or Redis). | Key format `idem:<hash>` with TTL aligned to throttle duration. |
+| `throttles` | Short-lived throttle tokens (PostgreSQL or Valkey). | Key format `idem:<hash>` with TTL aligned to throttle duration. |
 
 Records are stored using the canonical JSON serializer (`NotifyCanonicalJsonSerializer`) to preserve property ordering and casing. Schema migration helpers upgrade stored records when new versions ship.
 
@@ -101,7 +101,7 @@ Records are stored using the canonical JSON serializer (`NotifyCanonicalJsonSeri
   - `notify_delivery_attempts_total{channelType,status}`
   - `notify_digest_open_windows{window}`
   - Optional OpenTelemetry traces for rule evaluation and connector round-trips.
-- **Scaling levers.** Increase worker replicas to cope with bus throughput; adjust `worker.prefetchCount` for Redis Streams or `ackWait` for NATS JetStream. WebService remains stateless and scales horizontally behind the gateway.
+- **Scaling levers.** Increase worker replicas to cope with bus throughput; adjust `worker.prefetchCount` for Valkey Streams or `ackWait` for NATS JetStream. WebService remains stateless and scales horizontally behind the gateway.
 
 ---