## Why
Chunked blob uploads kept the in-progress session in **process memory** keyed by upload UUID, so the `POST`/`PATCH`/`PUT` of a single `docker push` had to land on the same replica. The API runs at `minReplicas: 2` with no session affinity (see argocd-apps `api-hpa.yaml`), so a real push — which streams the layer via `PATCH` then finalises with `PUT` — intermittently 404s with `BLOB_UPLOAD_UNKNOWN` when a chunk hits a replica that never saw the `POST`. This was flagged when the local docker registry landed (#103).
## Changes
- Stage chunked uploads in object storage under `uploads/<uuid>` instead of an in-memory temp file. The UUID travels in the `Location` URL handed to the client, so any replica reconstructs the staging key with no shared in-process state. Finalise streams the staged bytes plus any trailing `PUT` body through the CAS in one pass; monolithic uploads are unchanged.
- Support `DELETE` of an in-progress upload (cancel) by dropping its staging object.
- Reap abandoned staging objects in the GC (`uploads/` older than 24h) via a new `S3.ListStaleObjects`, so cancelled/interrupted pushes don't leak.
## Verification
- Split a single push across **two instances sharing one Postgres+MinIO**: `POST`→A, `PATCH`→B, `PUT`→A finalises with the correct digest, and the blob pulls back **byte-identical from both** replicas. Config-blob and manifest pushes split the same way succeed; `tags/list` is correct. (Pre-fix, the cross-replica `PATCH` 404s.)
- `scripts/docker-e2e.sh` still passes (incl. `TestLocalDockerPushPull`); unit tests + `go vet` clean.
Reviewed-on: #104
Co-authored-by: Ben Vincent <ben@unkin.net>
Co-committed-by: Ben Vincent <ben@unkin.net>
## Why
Local `docker` repos had no write path — the `/v2` Docker Registry API only proxied to upstreams. This makes a local docker repo a genuine container registry so `docker push`/`docker pull` (and podman/skopeo/buildah) work against it directly, matching the project principle that a local repo is *the real thing* rather than a mirror.
## Changes
- Implement the Docker Registry HTTP API V2 read/write half for local docker repos: blob uploads (monolithic and chunked POST/PATCH/PUT), manifest push, `tags/list`, and blob/manifest GET/HEAD.
- Store blobs and manifests through the existing content-addressable store; keep a `local_files` reference per (repo, image) so the GC does not reap them. Tags are mutable (`UpsertLocalFile`); digests and blobs are immutable.
- Dispatch `/v2` reads to the local handler for local docker repos and fall through to the upstream proxy otherwise; writes are local-docker only.
- Add `UpsertLocalFile` for mutable tag references.
- Cover the push/pull round-trip with a dockerised e2e test and unit-test the registry path parser. Document the registry in the README.
## Verification
- `scripts/docker-e2e.sh` passes, including the new `TestLocalDockerPushPull`.
- Verified a real end-to-end round-trip with skopeo against a live instance: pushed `hello-world`, pulled it back, loaded it into the docker daemon, and ran it successfully.
Reviewed-on: #103
Co-authored-by: Ben Vincent <ben@unkin.net>
Co-committed-by: Ben Vincent <ben@unkin.net>
unkinben