fix: feishu_doc create 支持同时写入内容，避免创建空文档

[lishuceo]

Summary

• feishu_doc 的 create action 此前只创建空文档，agent 需要分两步（create → write）才能写入内容
• 实际使用中 agent 经常只调 create 就返回结果，用户打开文档看到空内容
• 现在 create 接受可选 content 参数，创建后自动调用 markdownToBlocks 写入 Markdown 富文本内容
• 写入失败只 warn 不报错，确保文档创建本身不受影响

Test plan

• 新增测试：create with content 成功写入
• 新增测试：content 写入失败时文档仍创建成功
• 全部 26 个 doc tool 测试通过

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[claude]

Claude finished @lishuceo's task in 59s —— View job

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PR Review: fix: feishu_doc create 支持同时写入内容

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✅ Approved — Clean, well-scoped change.

What this PR does: Adds an optional content parameter to the create action in feishu_doc tool. When provided, content is written immediately after document creation using the existing markdownToBlocks + batchBlocks pipeline. Write failures are logged as warnings without failing the overall operation.

Review findings:

No issues found (confidence ≥ 75). Specifically verified:

• Correctness: The write logic reuses the same markdownToBlocks → batchBlocks → documentBlockChildren.create pattern used by write and append actions. Using doc.document_id as the block_id for a freshly created doc is consistent with the fallback behavior in write/append (pageBlock?.block_id ?? args.doc_token).
• Error handling: The warn-not-throw approach is a good design choice here — the user gets their document created and a token back, even if content write fails. The agent can retry the write separately.
• Schema/description updates: Both the Zod schema description and the tool description string are updated to reflect the new capability.
• Tests: Two new test cases cover the happy path (create with content) and the degraded path (content write fails, doc still created). Both correctly assert on the key behaviors.