[MergeDuplicates] Improve clarity of info for imported words/senses

[imnasnainaec]

A few suggestions from Hasso:

• The warning “This word was imported with data that The Combine does not handle . . .” should be shown on all affected entries, not only those with only one sense remaining. When I saw that I could move the senses of one entry but not another, I tried moving the senses, but when I got to the last sense, I could not move it. I would have liked to have known that the entry couldn’t be deleted before I started moving senses.
• The text of this error is too small to read (on Firefox 115.12.0esr on Wasta).

[jasonleenaylor]

Ask @papeh what the motivation is for having the warning when there is more than one sense remaining.

[imnasnainaec]

Ask @papeh what the motivation is for having the warning when there is more than one sense remaining.

Just asked in WhatsApp.

[imnasnainaec]

Ask @papeh what the motivation is for having the warning when there is more than one sense remaining.

Just asked in WhatsApp.

Updated the issue description with the response.