fix: correct multipart image merge path handling

__frzr-deploy

@@ -173,14 +173,19 @@ handle_multipart_image() {
     # 首先检查新格式（.partN-T）
     local first_part=$(find "$dir_name" -maxdepth 1 -type f -name "${base_name_no_ext}.part1-*.img.*" | head -n1)
     if [ -n "$first_part" ]; then
+		# 获取去除部分（partN-T）的实际后缀名
+		local real_ext=$(echo "$first_part" | sed "s/.*${base_name_no_ext}\.part1-[0-9]\+//")
+
+		local merged_file_name="${dir_name}/${base_name_no_ext}${real_ext}"
+
         # 从文件名中提取总部分数
         local total_parts=$(echo "$first_part" | grep -o 'part1-[0-9]*' | cut -d'-' -f2)
         echo "Found multipart image with $total_parts parts (new format)" >&2
 
         # 检查所有部分是否存在
         local missing_parts=0
         for ((i=1; i<=$total_parts; i++)); do
-            if [ ! -f "${dir_name}/${base_name_no_ext}.part${i}-${total_parts}.img."* ]; then
+            if [ ! -f "${dir_name}/${base_name_no_ext}.part${i}-${total_parts}${real_ext}" ]; then
                 echo "Missing part $i of $total_parts" >&2
                 missing_parts=1
                 break
@@ -194,18 +199,18 @@ handle_multipart_image() {
 
         # 合并文件
         echo "Merging parts..." >&2
-        : > "$base_file"  # 清空或创建目标文件
+        : > "$merged_file_name"  # 清空或创建目标文件
         for ((i=1; i<=$total_parts; i++)); do
-            cat "${dir_name}/${base_name_no_ext}.part${i}-${total_parts}.img."* >> "$base_file"
+            cat "${dir_name}/${base_name_no_ext}.part${i}-${total_parts}${real_ext}" >> "$merged_file_name"
         done
 
         # 清理分包文件
         echo "Cleaning up part files..." >&2
         for ((i=1; i<=$total_parts; i++)); do
-            rm -f "${dir_name}/${base_name_no_ext}.part${i}-${total_parts}.img."*
+            rm -f "${dir_name}/${base_name_no_ext}.part${i}-${total_parts}${real_ext}"
         done
 
-        echo "$base_file"
+        echo "$merged_file_name"
         return 0
     fi