fix: 构建前清理本地旧镜像，解决 buildx --load image already exists 错误

scripts/build_release_images.sh

@@ -60,6 +60,9 @@ fi
 # 默认只读不写，防止 feature 分支污染主缓存
 # 只有 develop/main 分支才写回缓存
 BRANCH_NAME="${GITHUB_REF_NAME:-${CI_COMMIT_BRANCH:-unknown}}"
+# 清理本地旧镜像
+docker rmi -f "$API_IMAGE" "$API_LATEST" 2>/dev/null || true
+
 if [ "$USE_CACHE" -eq 1 ]; then
   docker buildx build \
     --build-arg APP_VERSION="$VERSION" \
@@ -89,6 +92,9 @@ build_with_cache() {
     echo "  cache: read-only from ${CACHE_REGISTRY}/${IMG_NAME}-cache:${CACHE_TAG_PRIMARY}"
   fi
 
+  # 清理本地旧镜像，避免 buildx --load 报 already exists 错误
+  docker rmi -f "$IMG_NAME:$VERSION" 2>/dev/null || true
+
   if [ "$USE_CACHE" -eq 1 ]; then
     if [ -n "$CACHE_TO" ]; then
       docker buildx build \
@@ -119,6 +125,9 @@ build_with_cache "api" "infra/docker/api.Dockerfile" \
 docker tag "$API_IMAGE" "$API_LATEST"
 
 echo "=== Building Worker image ==="
+# 清理本地旧镜像
+docker rmi -f "$WORKER_IMAGE" "$WORKER_LATEST" 2>/dev/null || true
+
 if [ "$USE_CACHE" -eq 1 ]; then
   docker buildx build \
     --build-arg APP_VERSION="$VERSION" \
@@ -148,6 +157,9 @@ docker run --rm \
 
 test -f apps/web/dist/index.html
 
+# 清理本地旧镜像
+docker rmi -f "$WEB_IMAGE" 2>/dev/null || true
+
 if [ "$USE_CACHE" -eq 1 ]; then
   docker buildx build \
     --cache-from "type=registry,ref=${CACHE_REGISTRY}/web-cache:${CACHE_TAG_PRIMARY},ignore-error=true" \