feat: Implement Filesystem and MongoDB provenance writers for PackRun execution context

- Added `FilesystemPackRunProvenanceWriter` to write provenance manifests to the filesystem.
- Introduced `MongoPackRunArtifactReader` to read artifacts from MongoDB.
- Created `MongoPackRunProvenanceWriter` to store provenance manifests in MongoDB.
- Developed unit tests for filesystem and MongoDB provenance writers.
- Established `ITimelineEventStore` and `ITimelineIngestionService` interfaces for timeline event handling.
- Implemented `TimelineIngestionService` to validate and persist timeline events with hashing.
- Created PostgreSQL schema and migration scripts for timeline indexing.
- Added dependency injection support for timeline indexer services.
- Developed tests for timeline ingestion and schema validation.

docs/modules/notify/operations/dashboards/notify-observability.json

@@ -0,0 +1,6 @@
+{
+  "_note": "Placeholder Grafana dashboard stub for Notify. Replace panels when metrics endpoints are available; keep offline-import friendly.",
+  "schemaVersion": 39,
+  "title": "Notify Observability (stub)",
+  "panels": []
+}

docs/modules/notify/operations/observability.md

@@ -0,0 +1,38 @@
+# Notify observability runbook (stub · 2025-11-29 demo)
+
+## Dashboards (offline import)
+- Grafana JSON: `docs/modules/notify/operations/dashboards/notify-observability.json` (import locally; no external data sources assumed).
+- Planned panels: enqueue/dequeue rate, delivery latency p95/p99, channel error rate, retry/dead-letter counts, rule evaluation latency, tenant isolation breaches (should stay 0), and notification simulation outcomes.
+
+## Key metrics
+- `notify_enqueue_total{channel}` — notifications enqueued by channel.
+- `notify_delivery_latency_seconds_bucket{channel}` — delivery latency per channel.
+- `notify_delivery_failures_total{channel,reason}` — failed deliveries.
+- `notify_retry_total{channel}` and `notify_deadletter_total{channel}` — retries and dead letters.
+- `notify_rule_eval_duration_seconds_bucket` — rule evaluation latency.
+- `notify_simulation_total{result}` — simulation outcomes when quiet hours/correlation rules applied.
+
+## Logs & traces
+- Correlate by `notificationId`, `ruleId`, `tenant`, `channel`. Include `quietHoursApplied`, `correlationKey`, `retries` fields.
+- Traces disabled by default for air-gap; enable by pointing OTLP exporter to on-prem collector.
+
+## Health/diagnostics
+- `/health/liveness` and `/health/readiness` check queue backend reachability and channel provider credentials.
+- `/status` exposes build version, commit, feature flags; verify against offline bundle manifest.
+- Simulation probe: `/api/notify/simulate` with sample rule set to validate correlation/digest wiring once NOTIFY-SVC-39-001..004 land.
+
+## Alert hints
+- Delivery latency p99 > 1.5s for email/webhook channels.
+- Dead-letter queue growth > threshold.
+- Rule evaluation latency p99 > 500ms.
+- Correlation/quiet-hours simulation failures once enabled.
+
+## Offline verification steps
+1) Import Grafana JSON locally; point to Prometheus scrape labeled `notify`.
+2) Run `stella notify simulate --rules samples/rules.yaml --dry-run` (once available) and ensure metrics/logs emit locally.
+3) Fetch `/status` and compare commit/version to offline bundle manifest.
+
+## Evidence locations
+- Sprint tracker: `docs/implplan/SPRINT_322_docs_modules_notify.md`.
+- Module docs: `README.md`, `architecture.md`, `implementation_plan.md`.
+- Dashboard stub: `operations/dashboards/notify-observability.json`.