Fix controlled select reset behavior after form action

[xuanxuan321]

Summary

Fixes #30580

This PR fixes a bug where controlled <select> elements were being incorrectly reset after form submission when using form actions, while controlled <input> elements correctly maintained their values.

Problem

When a form with a controlled select element is submitted using a form action, React automatically calls form.reset() after the action completes. According to the HTML specification:

• Input elements read from the value attribute (corresponding to defaultValue property)
• Select elements read from option's selected attribute (corresponding to defaultSelected property)

React was syncing defaultValue for controlled inputs but not syncing defaultSelected for controlled selects. This caused selects to reset to an undefined state rather than maintaining their controlled value.

Solution

Modified three functions in ReactDOMSelect.js to sync the defaultSelected attribute for controlled select elements, making their behavior consistent with controlled inputs:

1. initSelect() - line 155
2. updateSelect() - line 224
3. restoreControlledSelectState() - line 241

Changed the setDefaultSelected parameter from false to true when value != null (controlled component).

Test Plan

• Added new test case: "controlled select elements maintain their value after form reset"
• All 45 ReactDOMForm tests pass ✅
• All 63 ReactDOMSelect tests pass ✅
• No regressions in existing functionality

How to Test

function App() {
  const [type, setType] = useState("2");
  
  return (
    <form action={async () => { /* async action */ }}>
      <select value={type} onChange={(e) => setType(e.target.value)}>
        <option value="1">1</option>
        <option value="2">2</option>
        <option value="3">3</option>
      </select>
    </form>
  );
}

Before fix: Select resets to first option after form submission
After fix: Select maintains the controlled value ✅

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