Function normalize_input_item 

pub fn normalize_input_item(
    item: &ResponseInputOutputItem,
) -> ResponseInputOutputItem

Normalize a SimpleInputMessage to a proper Message item

This helper converts SimpleInputMessage (which can have flexible content) into a fully-structured Message item with a generated ID, role, and content array.

SimpleInputMessage items are converted to Message items with IDs generated using the centralized ID generation pattern with “msg_” prefix for consistency.

Arguments

• item - The input item to normalize

Returns

A normalized ResponseInputOutputItem (either Message if converted, or original if not SimpleInputMessage)