fix(registry): use persistent local registry and OCI Distribution API image copy for pushes

readme.hints.md

@@ -108,6 +108,18 @@ tsdocker build --parallel --cached  # works with both modes
 
 Implementation: `Dockerfile.computeLevels()` groups topologically sorted Dockerfiles into dependency levels. `Dockerfile.runWithConcurrency()` provides a worker-pool pattern for bounded concurrency. Both are public static methods on the `Dockerfile` class. The parallel logic exists in both `Dockerfile.buildDockerfiles()` (standard mode) and `TsDockerManager.build()` (cached mode).
 
+## OCI Distribution API Push (v1.16+)
+
+All builds now go through a persistent local registry (`localhost:5234`) with volume storage at `.nogit/docker-registry/`. Pushes use the `RegistryCopy` class (`ts/classes.registrycopy.ts`) which implements the OCI Distribution API to copy images (including multi-arch manifest lists) from the local registry to remote registries. This replaces the old `docker tag + docker push` approach that only worked for single-platform images.
+
+Key classes:
+- `RegistryCopy` — HTTP-based OCI image copy (auth, blob transfer, manifest handling)
+- `Dockerfile.push()` — Now delegates to `RegistryCopy.copyImage()`
+- `Dockerfile.needsLocalRegistry()` — Always returns true
+- `Dockerfile.startLocalRegistry()` — Uses persistent volume mount
+
+The `config.push` field is now a no-op (kept for backward compat).
+
 ## Build Status
 
 - Build: ✅ Passes