tuwunel 1.9.4 exports no metrics. The host collector gets an httpcheck
receiver on the gateway's /_matrix/client/versions (new
services.hyperhive.otel.httpChecks, declared by hive-matrix), and a timer in
the hive-matrix container pushes the database directory's size through the
forwarder's OTLP port, as the attic cache-size unit does. The size step
dereferences the state directory's symlink and pushes nothing for a result
under 4096 bytes.
