fix(perf): bench jq direction bug + libaio + json note guard [#709]

- write tests read .write.* explicitly (jq // kept read=0 for writes)
- libaio1 installed everywhere (real aio engine, no sync cap)
- fio stdout notes stripped before jq parse

Ticket: https://projects.knownelement.com/issues/709

proxmox/perf/bench/Dockerfile

@@ -3,7 +3,7 @@
 FROM debian:12-slim
 
 RUN apt-get update -qq && apt-get install -y -qq --no-install-recommends \
-        fio iperf3 jq ca-certificates \
+        fio iperf3 jq libaio1 ca-certificates \
     && rm -rf /var/lib/apt/lists/*
 
 COPY bench-run.sh /usr/local/bin/bench-run.sh