feat(devcontainer): bake velero CLI into the toolbox, pinned to prod server v1.18.2

The velero CLI and server are version-coupled, so VELERO_VERSION follows the
server running on prod (docker.io/velero/velero:v1.18.2, chart 12.2.3,
verified 2026-11-07). It has no renovate marker on purpose: bump it together
with the chart's appVersion. The verify stage asserts that
`velero version --client-only` reports the pin. The build arg reaches CI
through build-image.sh --print-build-args, so no .gitea/ or ci/ change is
needed.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

infra/devcontainer/Containerfile

@@ -30,6 +30,9 @@ ARG CHECK_JSONSCHEMA_VERSION
 # Pinned to the Prometheus version prod actually runs — see versions.env for why that lockstep is
 # the point, and for the live-cluster command that establishes it.
 ARG PROMTOOL_VERSION
+# velero: operator CLI for the backup server. Pinned to the server version prod runs — the CLI
+# and server are version-coupled; see versions.env.
+ARG VELERO_VERSION
 ARG TARGETARCH=amd64
 
 # Distro packages: libvirt client libs (harmless disk-image utilities), ansible, ssh,
@@ -66,6 +69,10 @@ RUN set -eux; \
     curl -fsSL "https://dl.k8s.io/release/v${KUBECTL_VERSION}/bin/linux/${TARGETARCH}/kubectl" -o /usr/local/bin/kubectl; chmod +x /usr/local/bin/kubectl; \
     curl -fsSL "https://get.helm.sh/helm-v${HELM_VERSION}-linux-${TARGETARCH}.tar.gz" | tar -xz -C /tmp; \
       install -m0755 "/tmp/linux-${TARGETARCH}/helm" /usr/local/bin/helm; \
+    VELERO_TARBALL="velero-v${VELERO_VERSION}-linux-${TARGETARCH}"; \
+    curl -fsSL "https://github.com/vmware-tanzu/velero/releases/download/v${VELERO_VERSION}/${VELERO_TARBALL}.tar.gz" \
+      | tar -xz -C /usr/local/bin --strip-components=1 "${VELERO_TARBALL}/velero"; \
+      chmod +x /usr/local/bin/velero; \
     rm -rf /tmp/*
 
 # Pinned conformance test toolchain (L0/L1 static gate + the L2/L3 Chainsaw runner).
@@ -93,7 +100,7 @@ RUN { echo "opentofu=${OPENTOFU_VERSION}"; echo "age=${AGE_VERSION}"; echo "sops
       echo "kyverno=${KYVERNO_VERSION}"; echo "kyverno-json=${KYVERNO_JSON_VERSION}"; \
       echo "chainsaw=${CHAINSAW_VERSION}"; echo "yamllint=${YAMLLINT_VERSION}"; \
       echo "yq=${YQ_VERSION}"; echo "check-jsonschema=${CHECK_JSONSCHEMA_VERSION}"; \
-      echo "promtool=${PROMTOOL_VERSION}"; \
+      echo "promtool=${PROMTOOL_VERSION}"; echo "velero=${VELERO_VERSION}"; \
     } > /etc/dev-toolchain-versions
 
 WORKDIR /work
@@ -112,6 +119,7 @@ ARG KUBECTL_VERSION
 ARG CHAINSAW_VERSION
 ARG KYVERNO_VERSION
 ARG SOPS_VERSION
+ARG VELERO_VERSION
 RUN --network=none /bin/bash -euo pipefail <<'VERIFY'
 echo "--- no network (the build-time stand-in for run --network none) ---"
 if getent hosts registry.fedoraproject.org >/dev/null 2>&1 || curl -sS --max-time 3 -o /dev/null https://1.1.1.1 2>/dev/null; then
@@ -122,13 +130,13 @@ echo "--- baked versions ---"; cat /etc/dev-toolchain-versions
 echo "--- every tool is on PATH ---"
 for t in tofu age age-keygen sops flux kubectl helm kyverno kyverno-json chainsaw yq \
          yamllint check-jsonschema promtool ansible-playbook git make jq diff python3 \
-         wg qrencode; do
+         wg qrencode velero; do
   if command -v "$t" >/dev/null 2>&1; then printf "    ok      %s\n" "$t";
   else printf "    MISSING %s\n" "$t"; missing=1; fi
 done
 [ -z "${missing:-}" ] || { echo "toolbox is missing tools"; exit 1; }
 echo "--- version-sensitive tools report their pins ---"
-: "${PROMTOOL_VERSION:?}" "${KUBECTL_VERSION:?}" "${CHAINSAW_VERSION:?}" "${KYVERNO_VERSION:?}" "${SOPS_VERSION:?}"
+: "${PROMTOOL_VERSION:?}" "${KUBECTL_VERSION:?}" "${CHAINSAW_VERSION:?}" "${KYVERNO_VERSION:?}" "${SOPS_VERSION:?}" "${VELERO_VERSION:?}"
 check() { # name pin actual-output
   if printf "%s" "$3" | grep -qF "$2"; then printf "    ok      %-10s %s\n" "$1" "$2";
   else printf "    DRIFT   %-10s want %s, got: %s\n" "$1" "$2" "$(printf "%s" "$3" | head -1)"; drift=1; fi
@@ -138,6 +146,7 @@ check kubectl  "${KUBECTL_VERSION}"  "$(kubectl version --client 2>&1)"
 check chainsaw "${CHAINSAW_VERSION}" "$(chainsaw version 2>&1)"
 check kyverno  "${KYVERNO_VERSION}"  "$(kyverno version 2>&1)"
 check sops     "${SOPS_VERSION}"     "$(sops --version --disable-version-check 2>&1 || sops --version 2>&1)"
+check velero   "v${VELERO_VERSION}"  "$(velero version --client-only 2>&1)"
 [ -z "${drift:-}" ] || { echo "a tool does not report its pinned version"; exit 1; }
 echo "--- python can import what the renderer and the gate need ---"
 python3 -c "import yaml; print('    PyYAML', yaml.__version__)"