docs +create: Code blocks get a spurious trailing empty line 飞书文档中的代码块总是跟一个空白行

[OlorinMedas]

Summary

When creating a Feishu document from Markdown using lark-cli docs +create, every fenced code block in the resulting document gets an extra trailing empty line that does not exist in the source Markdown.

Steps to Reproduce

1. Prepare a Markdown file with a fenced code block:

   Some text before.
   
   ```
   line_one
   line_two
   ```
   
   Some text after.

2. Create a Feishu document:

   lark-cli docs +create --title "test" --content-file test.md

3. Open the created document in Feishu. The code block renders as:

   line_one
   line_two
   ⬇️ (unwanted blank line here)
   

Expected Behavior

The code block should contain exactly the lines from the source Markdown, with no extra trailing blank line.

Actual Behavior

Every code block has one extra empty line appended at the end. This is cosmetic but noticeable, especially when multiple code blocks are present — each one has the spurious blank line.

Investigation

The Markdown content passed to the API was confirmed correct (no trailing newline in the code block). The extra line appears to be introduced by the Lark OpenAPI document creation endpoint or the CLI's Markdown-to-block conversion layer.

Environment

• @larksuite/cli version: 1.0.0
• Platform: Windows 11
• Node.js: installed via npm global
• Brand: feishu

[PlayerNeo42]

同遇到这个问题，补充几个数据点，影响比原 issue 描述更严重：

补充发现

1. +update 同样受影响，不只 +create。
2. 往返会累积：每次 fetch → update 循环 +1 空行，线性叠加。

影响

基于「fetch → 修改 → 写回」模式的工具（AI agent、脚本化编辑）每次往返都会让代码块退化一次，长期维护的文档会堆积 3~5 个空行。调用方无法绕过，污染发生在往返过程内部。

复现（v1.0.5-30-g284e5b6）

# 1. 创建
lark-cli docs +create --title "t" --markdown $'```bash\necho hello\n```'

# 2. fetch → 多 1 个 \n
# "...echo hello\n\n```..."

# 3. 原样 overwrite 写回
lark-cli docs +update --doc <id> --mode overwrite --markdown "<fetched>"

# 4. 再 fetch → 多 2 个 \n
# "...echo hello\n\n\n```..."

定位

• CLI 层干净：fixExportedMarkdown 正确跳过代码块内容；+create / +update 只是把 markdown 透传给 MCP。
• 多余 \n 来自 MCP 服务端的 blocks↔markdown 转换，最可能是 fetch-doc 序列化代码块时多输出了一个 \n。

客户端规避

在 fixExportedMarkdown 加一个 trimCodeBlockTrailingBlanks 可以打断累积循环，但无法修复 +create 后那一个存入飞书服务端的空行。

[hunshcn]

ping @liangshuo-1 @caojie0621

[a5635268]

同样遇到，盼官方早日解决