Dynamic API-populated dropdown options for QApp input parameters

QApp input dialogs currently support only static, pre-defined dropdown lists for parameter selection, with no mechanism to refresh the available options from an external data source before the QApp runs. This enhancement would allow a QApp input to call an API at runtime to retrieve a current set of selectable values, populate the dropdown with those items, and let the user choose one before execution. Customers whose valid input values change frequently would be able to select accurate, up-to-date options without manually editing the QApp definition each time the underlying list changes, reducing maintenance effort and the risk of running a QApp against stale input values.