ci: make provider Docker pulls resilient

.github/scripts/docker-wait-for-health.sh

@@ -0,0 +1,47 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+if [ "$#" -lt 1 ] || [ "$#" -gt 3 ]; then
+  echo "Usage: $0 <container-with-health-check> [timeout-seconds] [poll-interval-seconds]" >&2
+  exit 2
+fi
+
+container="$1"
+timeout_seconds="${2:-60}"
+poll_interval_seconds="${3:-2}"
+deadline=$((SECONDS + timeout_seconds))
+
+while true; do
+  status="$(docker inspect --format '{{if .State.Health}}{{.State.Health.Status}}{{else}}none{{end}}' "$container")"
+
+  case "$status" in
+    healthy)
+      exit 0
+      ;;
+    unhealthy)
+      echo "Container ${container} is unhealthy." >&2
+      docker logs "$container" >&2 || true
+      exit 1
+      ;;
+    starting)
+      ;;
+    none)
+      echo "Container ${container} does not define a Docker health check." >&2
+      docker inspect "$container" >&2 || true
+      exit 1
+      ;;
+    *)
+      echo "Container ${container} has unexpected health status: ${status}" >&2
+      docker inspect "$container" >&2 || true
+      exit 1
+      ;;
+  esac
+
+  if [ "$SECONDS" -ge "$deadline" ]; then
+    echo "Container ${container} did not become healthy within ${timeout_seconds}s." >&2
+    docker logs "$container" >&2 || true
+    exit 1
+  fi
+
+  sleep "$poll_interval_seconds"
+done