chore(aiperf): bump submodule for _total counter-lookup fix

Pulls in cjq/agentx-v0.3-subagents @ 006417a8, which fixes a silent
regression in the realtime srv-row: counter lookups that included
`_total` (e.g. `vllm:prompt_tokens_total`, `sglang:prompt_tokens_total`)
never matched because `prometheus_client.parser` strips that suffix
before the data collector stores the family. Server-side throughput
rows were missing on every backend, not just SGLang — masked by unit
tests that bypassed the parser.

Signed-off-by: Cam Quilici <cjquilici@gmail.com>

Author: cquil11