Spec for integrating bincraft's ABI classifier (PR #49) into the iterative
and full build pipelines so only R-minor-sensitive packages are built per
installed R minor, leveraging the multi-R exec-env images.
## Summary
- Switches all 64 `.crow/*.yaml` workflows, the `Justfile`, and the commented-out `build-all-versions-install-deps.yaml` template to the new multi-R-version container images.
- Each image tag drops `-${R_VERSION}` (e.g. `build-env-alpine:3.22-4.5` → `build-env-alpine:3.22`); workflows pick an R version by calling `/opt/R/${R_VERSION}/bin/R` explicitly.
- Pattern-1 workflows (hard-coded image tag) gain a single `R_VERSION:` env var per file.
- Pattern-2 workflows (`build-all-versions-*`, matrix-driven) continue to receive `R_VERSION` via `crow pipeline create --var`.
## Platform → R_VERSION mapping
| Platform | Image | R_VERSION |
| --- | --- | --- |
| alpine 3.22 / 3.23 | `build-env-alpine:3.{22,23}` | 4.5.3 |
| ubuntu jammy / noble | `build-env-ubuntu:{jammy,noble}` | 4.4.3 |
| redhat 8 / 9 | `build-env-redhat:{8,9}` | 4.4.3 |
| redhat 10 | `build-env-redhat:10` | 4.5.3 |
The `alpine-321` audit-only workflows fall back to `build-env-alpine:3.23` since no 3.21 image exists in the new scheme; the audits only query S3/CRAN, so the container OS does not affect correctness.
## Bug fixes folded in
1. All six `weekly-audit-missing-alpine-*.yaml` files were pinned to `alpine:3.23-4.5` regardless of platform.
Now each one points at its own alpine image.
2. All fourteen `update-package-index-*.yaml` files were pinned to `build-env-ubuntu:noble-4.4` (or `noble-4.5` for `redhat-10-amd64`) regardless of platform.
Now each one uses its own platform's image.
3. `process-updates-ubuntu-2404-{amd64,arm64}.yaml` had `R_VERSION` of `4.4` (no patch) baked into the tag.
Aligned to `4.4.3`, matching the audit and rebuild counterparts.
## Smoke targets (post-merge)
One workflow per shape, ready to dry-run:
- `process-updates-alpine-322-amd64.yaml`
- `weekly-rebuild-missing-redhat-9-amd64.yaml`
- `weekly-audit-missing-ubuntu-2204-amd64.yaml`
- `update-package-index-redhat-10-amd64.yaml`
- `archive-missed-packages.yaml`
- `build-all-versions-amd64.yaml` (with its install-deps predecessor)
- `build-r-minor-sensitive-packages.yaml`
## Follow-ups (out of scope, surfaced during review)
- `process-updates-redhat-10-{amd64,arm64}.yaml` set `codename = "rhel9"` in their `upload_package_index(...)` calls.
Pre-existing bug — should be `"rhel10"`. The `update-package-index-redhat-10-*` counterparts already use `"rhel10"` correctly.
- `update-package-index-redhat-8-amd64.yaml` is missing the `packageVersion("bincraft")` diagnostic line that every sibling file has.
Pre-existing asymmetry between amd64 and arm64.
## Spec & plan
- Spec: `docs/superpowers/specs/2026-05-25-multi-r-version-images-design.md`
- Plan: `docs/superpowers/plans/2026-05-25-multi-r-version-images.md`
Reviewed-on: #70
