ci: mover data-root de Docker a /mnt en las lanes runtime (No space left on device)

parity-runtime falló con "No space left on device": la matriz runtime
construye muchas imágenes reales y `ubuntu-latest` sólo trae ~14GB libres
en / (donde vive /var/lib/docker y los logs del runner).

Se mueve el data-root de Docker a /mnt (disco efímero grande del runner,
~70GB) en el mismo daemon.json donde ya se activa el containerd image
store, y se eliminan SDKs preinstalados sin usar (dotnet/ghc/android)
para dar aire al disco raíz. Aplica a parity-runtime y a la lane arm64
experimental.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: aledbf

.github/workflows/go-cli.yml

@@ -111,13 +111,21 @@ jobs:
       - uses: actions/checkout@v7
         with:
           submodules: recursive
-      # The runtime matrix builds with cache export / --platform, unsupported by the
-      # default docker driver. Enable the containerd image store on the daemon.
-      - name: Enable containerd image store
+      # ubuntu-latest ships only ~14GB free on / but a large ephemeral disk on /mnt.
+      # The runtime matrix builds many real images; keeping Docker's data-root on /
+      # exhausts it ("No space left on device"). Move data-root to /mnt and, in the
+      # same daemon config, enable the containerd image store (needed for cache
+      # export / --platform, unsupported by the default docker driver). Also drop
+      # unused preinstalled SDKs to give the root disk headroom (Go/Node are
+      # reinstalled by the setup steps that follow).
+      - name: Configure Docker (data-root on /mnt, containerd store) + free disk
         run: |
-          echo '{"features":{"containerd-snapshotter":true}}' | sudo tee /etc/docker/daemon.json
+          sudo rm -rf /usr/share/dotnet /opt/ghc /usr/local/lib/android || true
+          sudo mkdir -p /mnt/docker
+          echo '{"features":{"containerd-snapshotter":true},"data-root":"/mnt/docker"}' | sudo tee /etc/docker/daemon.json
           sudo systemctl restart docker
-          echo "driver status:" && docker info -f '{{.DriverStatus}}'
+          docker info -f 'root={{.DockerRootDir}} driver={{.DriverStatus}}'
+          df -h / /mnt
       - uses: actions/setup-go@v6
         with:
           go-version-file: go.mod
@@ -163,10 +171,14 @@ jobs:
         uses: docker/setup-qemu-action@v3
         with:
           platforms: arm64
-      - name: Enable containerd image store
+      - name: Configure Docker (data-root on /mnt, containerd store) + free disk
         run: |
-          echo '{"features":{"containerd-snapshotter":true}}' | sudo tee /etc/docker/daemon.json
+          sudo rm -rf /usr/share/dotnet /opt/ghc /usr/local/lib/android || true
+          sudo mkdir -p /mnt/docker
+          echo '{"features":{"containerd-snapshotter":true},"data-root":"/mnt/docker"}' | sudo tee /etc/docker/daemon.json
           sudo systemctl restart docker
+          docker info -f 'root={{.DockerRootDir}} driver={{.DriverStatus}}'
+          df -h / /mnt
       - uses: actions/setup-go@v6
         with:
           go-version-file: go.mod