Passive per-allocation QoS and metering exporter.
Counts byte_size(payload) on every frame. Telemetry events:
[:xturn, :metrics, :allocation, :sample]— periodic flush[:xturn, :metrics, :allocation, :stop]— final snapshot fromhandle_close/2
Options
:flush_ms— sample interval in milliseconds (default5000):clock_rates— payload type to clock rate map (default%{0 => 8000, 8 => 8000}):usage_log— optional path; one JSON line appended per allocation on stop:match— allocation filter passed toattach?/2