[MergeDups] Data loss when merging then splitting

[imnasnainaec]

• Create two words with the same vernacular form but different glosses
• Add a pronunciation audio recording to one of the entries
• Go to Merge Duplicates
• Drag the sense from the word with 1 audio into the other word
• See that the 1 audio is moved to the single word
• Drag the sense that you moved to the empty column to create a new word for it
• The interface indicates that the audio does not move with it, but stays with the word it was first moved to
• Click the Save & Continue button
• Go to Review Entries
• Neither of the two words has the audio---it's been lost!

[imnasnainaec]

If we choose to allow data to be lost in this sort of odd maneuver, that's okay, as long as the interface accurately reflects what will happen. Showing audio before a Save & Continue that doesn't actually save the audio is bad.