v3.14.7 — bump pibox v0.11.3 → v0.12.0

Image-tag bump only. Base tracked to psyb0t/aicodebox:v0.11.0.

Upstream behavior change: /openai/v1/chat/completions returns
HTTP 400 with the provider's error message on provider rejection
(content-safety filter / rate limit / auth failure) instead of
HTTP 200 with empty completion body. Pi reports the underlying
detail as stopReason=error + errorMessage on the assistant turn.

Aigate impact: LiteLLM's proxy sees a real 4xx and retries per
its num_retries + fallback chain instead of ambiguous phantom
success reaching the caller. No API / env / config change on the
aigate side.

HEADS-UP: psyb0t/pibox:v0.12.0 + psyb0t/aicodebox:v0.11.0 may not
be on Docker Hub at this tag's cut moment.