## Why

AssetAZ needs an authoritative durable event history from which services can reconstruct their models and establish causal freshness. Gitea issue #86 defines a deliberately strict first version.

## What Changes

- Add an append-only PDE journal with SHA-256 integrity, durable sequence commitment and fail-closed writes.
- Add domain events and registry-provided positional event codecs, independent of Java class naming.
- Add independent virtual-thread subscriptions, replay, exact filtering, progress barriers and isolated degradation.
- Add reusable bounded PDE primitive encoding and decoding.

## Capabilities

### New Capabilities
- `assetaz-journal`: Persistence, event schemas, replay and consumer consistency contracts.
- `pde-encoding`: Minimal bounded PDE primitives and object framing.

### Modified Capabilities

None.

## Impact

New AssetAZ API and reference implementation packages, a reusable PDE library, and explicit codec/process entries in the existing Hub composition root. No new dependencies. The Nenjim artifact journal is separate and unchanged.

## Non-goals

No snapshots, repair, truncation, retries, consumer recovery, unregister, restart support, adaptive limits, pools, generalized serialization, reflection discovery, migration, PDL, signatures, causation IDs or unrelated thread changes.