realTimeErrorCount was only ever written as 0, so the status screen,
diagnostics and the status API always said there were no real-time
errors. When the change listener records failed events it now adds
their number to the table's count (after commit, serialized in the JVM,
never failing the user's write). A successful basepull or full reindex
resets it; the field's help text says so.
Fixes#53
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>