hasFreeSpace
Indicates whether there is free space available in the channel for additional write operations.
This property checks if the current size of the flush buffer is less than the predefined maximum channel size. If true, it means there is space available for more data to be written to the channel without requiring an immediate flush.
Note: This is an internal API and subject to change or removal without notice. If you need to use this property, please share your use case with us at KTOR-9579.
Return
true if there is free space in the flush buffer; false otherwise.