Don't garbage collect voicemails in AnnotatedCallLog.

We currently limit the size of AnnotatedCallLog to 999 via a trigger, but it doesn't exclude voicemails. Since we don't want to ever garbage collect the user's voicemails, exclude them from the trigger.

This means that we can no longer assume a maximum size for the table (the user culd have more than 999 voicemails) so I've updated the places in the code where we did that before.

Finally, I changed AnnotatedCallLog's CALL_TYPE column to be non-null. This is so that we can have more confidence that the trigger will work as intended. Null values cannot be compared in SQLite, so an expression like "where call_type != 4" won't actually match a null call type. Rather than implicitly fail to clean up such rows, we just crash completely when encountering such rows (even though I don't expect that to happen).

Bug: 70989634
Test: unit
PiperOrigin-RevId: 183006714
Change-Id: I9f4394a4812afe4b65c1e8427c355d825356557c