v0.2.0

Since v0.1.0:
- GPU support: stage using(special="gpu[:N]") -> accelerator N (AWS Batch/HealthOmics).
- Runtime fidelity: OOM memory escalation on retry (--auto-adjust-memory),
  preflight pipeline gating, array<map<S>>.field projection, split-returned
  __special routing, and declared vmem_gb enforced under --monitor.
- Tooling: 'mro2nf overrides' converts mrp --overrides to a Nextflow -c config;
  RUNTIME_TUNING.md maps the remaining mrp knobs to Nextflow.
- Release: multi-arch runtime base image published to ghcr.io/eunmann/mro2nf-runtime.
- CI: lint/e2e green under branch protection; squash-merge workflow.