bus-bench: raw CAN over MQTT, measured on the car Orin

SocketCAN to yukart/can/raw and back, per frame or batched, with loss and
latency from the kernel timestamp. No loss at a saturated 500 kbit/s bus;
batched costs the broker ~1 % of a core. Report in docs/impl/reports.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DDwfd6Ki8UfG4hK6W5YpJz

Cargo.toml

@@ -13,6 +13,10 @@ path = "src/recorder/main.rs"
 name = "orin-status"
 path = "src/orin-status/main.rs"
 
+[[bin]]
+name = "bus-bench"
+path = "src/bus-bench/main.rs"
+
 [dependencies]
 libc = "0.2"
 rumqttc = { version = "0.25", default-features = false }