limeTRX drops samples on a partial Tx and ignores output file failures #405

Transmit. Each iteration reads samplesToSend samples from the file but decrements the remaining count by what Transmit actually accepted:

int32_t samplesSent = args->stream->Transmit(txSamples, samplesToSend, &txMeta);
txMeta.timestamp.AddTicks(samplesSent);
samplesRemaining -= samplesSent;

StreamTxTemplate legitimately returns less than count (including 0) when the Tx FIFO push times out. The unsent tail of the chunk is never retransmitted - the next read fetches the following chunk - so samples are silently skipped and the file position desynchronizes from samplesRemaining.

Output file. rxFile.open(rxFilename + ".sigmf-data", ...) is never checked, nor is the .sigmf-meta open. Every later write on the failed stream is a no-op and main still returns 0, so a capture to an unwritable path is discarded while the tool reports success.