writeFramed
suspend fun <T> L2capChannel.writeFramed(value: T, encoder: BleEncoder<T>, framer: Framer = LengthPrefixFramer())
Encode a value, frame the bytes, and write the framed packet.
Pairs with framedIncoming. The framer prefixes the encoded payload with a length header so the receiver can recover boundaries independent of how the transport delivers chunks. Throws if the encoded payload exceeds the framer's maxFrameSize; no bytes are written in that case.