Busboy结合Firebase/Firestorage上传图片失败问题求助

将近6周以来，我尝试了Firebase-Admin、Node.js、Busboy、Multer等多种工具组合上传图片到Firebase，但全部失败。甚至求助了ChatGPT插件Grimoire也没能解决，始终抛出同一个错误：

Error uploading: Error: Unexpected end of form
      at Multipart._final (/Users/user/Desktop/project-Functions/functions/node_modules/busboy/lib/types/multipart.js:588:17)
      at prefinish (node:internal/streams/writable:906:14)
      at finishMaybe (node:internal/streams/writable:920:5)
      at Writable.end (node:internal/streams/writable:835:5)
      at onend (node:internal/streams/readable:946:10)
      at process.processTicksAndRejections (node:internal/process/task_queues:77:11) {
    storageErrors: []

我的核心代码逻辑如下（尝试过多种写法，核心逻辑一致）：

app.post("/uploadProfilePicture", upload.single("profileImage"), (req, res) => {
    const file = req.file;
    const { originalname, buffer } = file;
    const blob = bucket.file("profile_pictures/" + originalname);
    const blobStream = blob.createWriteStream({
        metadata: {
            contentType: file.mimetype,
        },
    });

    blobStream.on("error", (err) => {
        console.error(err);
        res
            .status(500)
            .send({ message: "Failed to upload image.", error: err.toString() });
    });

    blobStream.on("finish", () => {
        const publicUrl = `https://storage.googleapis.com/${bucket.name}/${blob.name}`;
        res
            .status(200)
            .send({ message: "Image uploaded successfully", url: publicUrl });
    });

    blobStream.end(buffer);
});

内容的提问来源于stack exchange，提问作者lamb p