ui builder client script ,UX Client Script Include

[kack l]

I'm working on a "furigana auto-generation" feature in UI Builder on ServiceNow Workspace.
In a Client Script (onChange event), I wrote the following code:
,UX Client Script Include：

function include({ imports }) {
console.log('✅ AutoKanaUtil 被载入');

const kanjiToHiragana = {
'髙': 'たか', '山': 'やま',
'養': 'よう', '蜂': 'ほう', '場': 'じょう',
};

function convertKana(input) {
console.log('🔠 convertKana 被呼び出された:', input);
if (typeof input !== 'string') return '';

let result = '';
for (let char of input) {
if (kanjiToHiragana[char]) {
result += kanjiToHiragana[char];
} else {
result += char;
}
}

return result;
}

return {
convertKana
};
}

ui builder client scrip：

function handler({ api, event, imports }) {

  console.log('🔍 onChange triggered with value:', event.payload?.value);

  console.log('📦 imports object:', imports);

  try {

    const kanaUtil = imports['sn_cwf_wrkspc.AutoKanaUtil']();

    if (!kanaUtil || typeof kanaUtil.convertKana !== 'function') {

      console.error('❌ convertKana ');

      return;

    }

    const inputValue = event.payload?.value || '';

    const kana = kanaUtil.convertKana(inputValue);

    console.log('✅ kana result:', kana);

    if (api.record) {

      api.record.u_hurikana = kana;     // api.record.setValue('u_hurikana', kana);

    } else if (event.record) {

      event.record.u_hurikana = kana;

    } else {

      console.error('No record object available—check the API docs for the proper setter.');

    }

  } catch (e) {

    console.error('❌ ', e);

  }

}

However, this causes a runtime error:❌ Error: TypeError: Cannot set properties of undefined (setting 'u_hurikana')

Should I use something like api.record.u_hurikana = kana instead?

I would appreciate any clarification regarding limitations or best practices for modifying field values within UI Builder Client Scripts.