refactor(ci): consolidate build-all-versions workflows into 2 files (#93)

## Summary

Consolidate the four `build-all-versions*` files into two, mirroring the matrix approach used for the process-updates / weekly families:

| Before | After |
|---|---|
| `build-all-versions-amd64.yaml` + `build-all-versions-arm64.yaml` | `build-all-versions.yaml` |
| `build-all-versions-install-deps-amd64.yaml` + `-arm64.yaml` | `build-all-versions-install-deps.yaml` |

`ARCH` becomes a matrix axis carrying the per-arch differences: `agent` (artemis/gaia), `BACKEND` (kubernetes/docker), and `R_PKG_CACHE_DIR`. Build-all keeps its `SPLIT_INDEX` parallelism, so its matrix is ARCH x SPLIT = 8 rows; only the rows matching the selected arch run.

**Invocation unchanged.** Routing uses the existing task selector `task == "build-all-${ARCH}"`, so `--var task=build-all-amd64 ...` still runs exactly the amd64 rows. `OS` / `OS_VERSION` / `R_VERSION` / `K8S_INSTANCE_TYPE` are still passed via `--var`. (You can drop `--var ARCH=...` now — arch comes from the matrix/task.)

**No cron.** These pipelines are manual-only, so there are no scheduled runs to affect.

## Validation before merge

Same matrix-interpolation-in-`when`/`labels` mechanism validated for #92, plus it now relies on per-row `agent`/`BACKEND` selecting the right execution backend (kubernetes for amd64, docker for arm64). Before merge, on this branch trigger a small `task=build-all-arm64` run and confirm it lands on the gaia/docker backend (and amd64 on artemis/kubernetes). Originals are in git history for rollback.

Note: `archive-missed-packages.yaml` was already a single consolidated matrix file (cron + manual) and is left untouched.
Reviewed-on: #93

.crow/build-all-versions-install-deps.yaml

@@ -1,11 +1,43 @@
+# Consolidated install-deps for build-all (both arches in one file).
+# Triggered together with build-all-versions; `target_arch` routes the matrix.
+# Variables are declared so the manual-run form exposes them (crow #1165);
+# they are merged with build-all-versions' identical declarations.
+variables:
+  target_arch:
+    description: "Architecture to build."
+    options:
+      - amd64
+      - arm64
+    default: amd64
+  OS:
+    description: "Base OS image name (e.g. alpine, redhat, ubuntu)."
+    default: alpine
+  OS_VERSION:
+    description: "OS version / image tag (e.g. 3.24, 9, jammy, noble)."
+    default: "3.24"
+  R_VERSION:
+    description: "Primary R version under /opt/R."
+    options:
+      - 4.5.3
+      - 4.4.3
+    default: 4.5.3
+
 when:
   - event: manual
-    evaluate: 'task == "build-all-arm64"'
+    evaluate: 'target_arch == "${ARCH}"'
 
 skip_clone: true
 
 labels:
-  agent: gaia
+  platform: linux/${ARCH}
+  agent: ${AGENT}
+
+matrix:
+  include:
+    - ARCH: amd64
+      AGENT: artemis
+    - ARCH: arm64
+      AGENT: gaia
 
 steps:
   - name: 'Install deps and bincraft'
@@ -41,16 +73,3 @@ steps:
           requests:
             memory: 5Gi
             cpu: 1000m
-      kubernetes:
-        resources:
-          requests:
-            memory: 5Gi
-            cpu: 1000m
-        nodeSelector:
-          kubernetes.io/arch: ${ARCH}
-          node.kubernetes.io/instance-type: ${K8S_INSTANCE_TYPE}
-        tolerations:
-          - key: 'CI'
-            operator: 'Equal'
-            value: 'true'
-            effect: 'NoSchedule'

.crow/build-all-versions.yaml

@@ -1,55 +1,83 @@
-### Required extra vars
-# ARCH (amd64)
-# OS (alpine)
-# OS_VERSION (3.22)
-# R_VERSION (4.5.3)
+### Manual full rebuild of all CRAN binaries for one OS/arch.
+# Set the variables below in the manual-run form (or via --var on the CLI).
+# `target_arch` routes the matrix; OS/OS_VERSION/R_VERSION select the platform
+# image and cache volume. Placement is via the agent label (artemis/gaia).
 # Skip list lives in local/excluded-packages.json (read by local/build-all.R).
-# crow pipeline create --var ARCH=arm64 --var OS=alpine --var OS_VERSION=3.24 --var R_VERSION=4.5.3 --var task=build-all-arm64 --branch=main --log-level=info 5
-# crow pipeline create --var ARCH=arm64 --var OS=alpine --var OS_VERSION=3.24 --var R_VERSION=4.5.3 --var task=build-all-arm64 --branch=main --log-level=info 5
+variables:
+  target_arch:
+    description: "Architecture to build."
+    options:
+      - amd64
+      - arm64
+    default: amd64
+  OS:
+    description: "Base OS image name (e.g. alpine, redhat, ubuntu)."
+    default: alpine
+  OS_VERSION:
+    description: "OS version / image tag (e.g. 3.24, 9, jammy, noble)."
+    default: "3.24"
+  R_VERSION:
+    description: "Primary R version under /opt/R."
+    options:
+      - 4.5.3
+      - 4.4.3
+    default: 4.5.3
+
 when:
   - event: manual
-    evaluate: 'task == "build-all-arm64"'
+    evaluate: 'target_arch == "${ARCH}"'
 
 skip_clone: true
 
 labels:
-  agent: gaia
+  platform: linux/${ARCH}
+  agent: ${AGENT}
 
 matrix:
   include:
-    # - SPLIT_INTO: 5
-    #   SPLIT_INDEX: 1
-    #   BACKEND: kubernetes
-    # - SPLIT_INTO: 5
-    #   SPLIT_INDEX: 2
-    #   BACKEND: kubernetes
-    # - SPLIT_INTO: 5
-    #   SPLIT_INDEX: 3
-    #   BACKEND: kubernetes
-    # - SPLIT_INTO: 5
-    #   SPLIT_INDEX: 4
-    #   BACKEND: kubernetes
-    # - SPLIT_INTO: 5
-    #   SPLIT_INDEX: 5
-    #   BACKEND: kubernetes
-    - SPLIT_INTO: 4
+    - ARCH: amd64
+      AGENT: artemis
+      R_PKG_CACHE_DIR: ''
+      SPLIT_INTO: 4
       SPLIT_INDEX: 1
-      BACKEND: docker
-    - SPLIT_INTO: 4
+    - ARCH: amd64
+      AGENT: artemis
+      R_PKG_CACHE_DIR: ''
+      SPLIT_INTO: 4
       SPLIT_INDEX: 2
-      BACKEND: docker
-    - SPLIT_INTO: 4
+    - ARCH: amd64
+      AGENT: artemis
+      R_PKG_CACHE_DIR: ''
+      SPLIT_INTO: 4
       SPLIT_INDEX: 3
-      BACKEND: docker
-    - SPLIT_INTO: 4
+    - ARCH: amd64
+      AGENT: artemis
+      R_PKG_CACHE_DIR: ''
+      SPLIT_INTO: 4
+      SPLIT_INDEX: 4
+    - ARCH: arm64
+      AGENT: gaia
+      R_PKG_CACHE_DIR: /mnt/cache/pkgcache
+      SPLIT_INTO: 4
+      SPLIT_INDEX: 1
+    - ARCH: arm64
+      AGENT: gaia
+      R_PKG_CACHE_DIR: /mnt/cache/pkgcache
+      SPLIT_INTO: 4
+      SPLIT_INDEX: 2
+    - ARCH: arm64
+      AGENT: gaia
+      R_PKG_CACHE_DIR: /mnt/cache/pkgcache
+      SPLIT_INTO: 4
+      SPLIT_INDEX: 3
+    - ARCH: arm64
+      AGENT: gaia
+      R_PKG_CACHE_DIR: /mnt/cache/pkgcache
+      SPLIT_INTO: 4
       SPLIT_INDEX: 4
-      BACKEND: docker
-    # - SPLIT_INTO: 5
-    #   SPLIT_INDEX: 5
-    #   BACKEND: docker
 
 depends_on:
-  - build-all-versions-install-deps-arm64
+  - build-all-versions-install-deps
 
 steps:
   - name: 'Build binaries'
@@ -71,7 +99,7 @@ steps:
       # normal env vars
       GIT_USER: pat-s
       # set the location of the 'pkgcache' cache dir which persists the R package dependencies needed to install the packages themselves
-      R_PKG_CACHE_DIR: /mnt/cache/pkgcache
+      R_PKG_CACHE_DIR: ${R_PKG_CACHE_DIR}
       R_LIBS_USER: /mnt/cache/R-pkgs
       CCACHE_DIR: /mnt/cache/ccache
       NCPUS: 2
@@ -105,22 +133,6 @@ steps:
           limits:
             memory: 20Gi
             cpu: 2000m
-      kubernetes:
-        resources:
-          requests:
-            memory: 5Gi
-            cpu: 1000m
-          limits:
-            memory: 20Gi
-            cpu: 2000m
-        nodeSelector:
-          kubernetes.io/arch: ${ARCH}
-          node.kubernetes.io/instance-type: ${K8S_INSTANCE_TYPE}
-        tolerations:
-          - key: 'CI'
-            operator: 'Equal'
-            value: 'true'
-            effect: 'NoSchedule'
   - name: 'Upload package indexes'
     image: 'reg.devxy.io/rpkgs/build-env-${OS}:${OS_VERSION}'
     pull: true
@@ -148,20 +160,4 @@ steps:
             cpu: 1000m
           limits:
             memory: 20Gi
-            cpu: 2000m
-      kubernetes:
-        resources:
-          requests:
-            memory: 5Gi
-            cpu: 1000m
-          limits:
-            memory: 20Gi
-            cpu: 2000m
-        nodeSelector:
-          kubernetes.io/arch: ${ARCH}
-          node.kubernetes.io/instance-type: ${K8S_INSTANCE_TYPE}
-        tolerations:
-          - key: 'CI'
-            operator: 'Equal'
-            value: 'true'
-            effect: 'NoSchedule'
+            cpu: 2000m