The frame was popped before queueTx(), so whenever the radio queue was busy
it was lost. Peek it instead, only remove it once it is queued (or TX is
suspended), and don't try while the queue has no room. The repeater buffer
moves to TxBuffer.h/.cpp so it can be unit tested.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
