fix(iotracing): export max block latencies

[pkurunner]

Summary

• update iotracing BPF to maintain max q2c/d2c latency counters
• expose max_q2c_us and max_d2c_us in JSON output
• include max latency values in the text table output

Testing

• gofmt -w cmd/iotracing/aggregate.go cmd/iotracing/format.go pkg/types/iotracing.go
• go test ./pkg/types
• Not run: GOOS=linux GOARCH=amd64 go test -c ./cmd/iotracing is blocked on a clean upstream snapshot by missing generated internal/toolstream/transport capnp types.
• Not run: BPF build / clang-format because clang is not available on this Windows machine.