fix(ci): buildx本地缓存损坏自动检测+清理重试，根治snapshot not found连锁失败

- 新增build_with_cache_retry()函数：检测缓存损坏类错误自动清理本地缓存并重试
- 覆盖错误模式：parent snapshot not found、cache corrupt、failed to compute cache key
- 两级降级：本地缓存重试1次 → 完全不用本地缓存只用registry缓存
- 同时清理buildx builder内部snapshot状态（docker buildx prune -a）
- 非缓存类错误直接透传，不误重试

scripts/ci/docker_build_push.sh

@@ -28,27 +28,64 @@ LOCAL_CACHE_DIR="/tmp/buildx-cache/${CACHE_NAME}"
 
 mkdir -p "$LOCAL_CACHE_DIR"
 
-# 缓存源：local优先，registry兜底
-CACHE_FROM_LOCAL="type=local,src=${LOCAL_CACHE_DIR}"
-CACHE_FROM_REGISTRY="type=registry,ref=${CACHE_REF},ignore-error=true"
+# 缓存源：local优先（带自动修复），registry兜底
+# 本地缓存损坏时自动清理后重试，避免snapshot not found导致构建全挂
+build_with_cache_retry() {
+  local attempt=1
+  local max_attempts=2
+  while [ $attempt -le $max_attempts ]; do
+    local build_output
+    local exit_code
+    set +e
+    build_output=$(docker buildx build \
+      $BUILD_ARGS \
+      --cache-from "type=local,src=${LOCAL_CACHE_DIR}" \
+      --cache-from "type=registry,ref=${CACHE_REF},ignore-error=true" \
+      --cache-to "type=local,dest=${LOCAL_CACHE_DIR},mode=max" \
+      -f "${DOCKERFILE}" \
+      -t "${IMAGE_TAG}" \
+      --push \
+      . 2>&1)
+    exit_code=$?
+    set -e
+    if [ $exit_code -eq 0 ]; then
+      echo "$build_output"
+      return 0
+    fi
+    # 检测到缓存损坏类错误，清掉本地缓存重试
+    if echo "$build_output" | grep -qE "parent snapshot.*not found|snapshot.*does not exist|cache.*corrupt|failed to compute cache key"; then
+      echo "$build_output"
+      echo ""
+      echo "⚠️  Local cache appears corrupted, cleaning up and retrying (attempt $attempt/$max_attempts)..."
+      rm -rf "${LOCAL_CACHE_DIR}"
+      mkdir -p "${LOCAL_CACHE_DIR}"
+      # 清理buildx builder的内部snapshot状态
+      docker buildx prune -f -a >/dev/null 2>&1 || true
+      attempt=$((attempt + 1))
+    else
+      # 非缓存类错误，直接输出并返回
+      echo "$build_output"
+      return $exit_code
+    fi
+  done
+  # 重试完还是失败，不用本地缓存最后试一次（只从registry读）
+  echo "⚠️  All cached attempts failed, building without local cache..."
+  docker buildx build \
+    $BUILD_ARGS \
+    --cache-from "type=registry,ref=${CACHE_REF},ignore-error=true" \
+    --cache-to "type=local,dest=${LOCAL_CACHE_DIR},mode=max" \
+    -f "${DOCKERFILE}" \
+    -t "${IMAGE_TAG}" \
+    --push \
+    .
+}
 
-# 本地缓存目标（必选，mode=max最大化命中率）
-CACHE_TO_LOCAL="type=local,dest=${LOCAL_CACHE_DIR},mode=max"
-
-echo "=== Step 1: Build & push image (local cache read-write + registry read) ==="
+echo "=== Step 1: Build & push image (local cache + registry read, with auto-repair) ==="
 echo "Local cache: ${LOCAL_CACHE_DIR}"
 echo "Registry cache: ${CACHE_REF}"
 echo ""
 
-docker buildx build \
-  $BUILD_ARGS \
-  --cache-from "${CACHE_FROM_LOCAL}" \
-  --cache-from "${CACHE_FROM_REGISTRY}" \
-  --cache-to "${CACHE_TO_LOCAL}" \
-  -f "${DOCKERFILE}" \
-  -t "${IMAGE_TAG}" \
-  --push \
-  .
+build_with_cache_retry
 
 echo ""
 echo "Image pushed: ${IMAGE_TAG}"