People Directory search returns inconsistent results

The number of results reported in "Found N results for query <name>" doesn't match up with the number of results actually returned via pagination, implying that two different searches are being performed.

Reported in CSP-13368. The EXTERNAL_ENTITY table is implicated: it looks like this is incorrectly queried when returning the total number of users with a matching name.

This isn't a duplicate of [CONF-6389], as it's not a simple multiple of the number of users found, however it may be related to or a duplicate of CONF-9455.