uas-platform/frontend/uas-web/overrides/form/field/Date.js

Ext.define('uas.override.form.field.Date', {
    override: 'Ext.form.field.Date',
    
    format: 'Y-m-d',

    setValue: function (v) {
        if (v && Ext.isString(v)) {
            v = new Date(v);
        }

        this.callParent([v]);
    }
});