### Check for existing issues

- [x] I have searched the existing issues and checked that my issue is not a duplicate.

### What happened?

## What happened?

All replicas of our LiteLLM proxy (Docker Swarm, 4 replicas) entered a continuous crash-loop: every container was killed with `task: non-zero exit (137): dockerexec: unhealthy container` every 4–8 minutes, around the clock, for 26+ hours.

Root cause (confirmed with **five py-spy dumps across four different containers**): whenever a request with a **large payload fails** (provider 4xx/5xx), the exception string — which embeds the original request/response body — is passed through `litellm/litellm_core_utils/secret_redaction.py::redact_string()`. One of the compiled patterns exhibits **catastrophic backtracking** on large, brace-heavy input. The `re.sub()` call runs **synchronously on the asyncio event loop**, holding the GIL for **minutes**, during which:

- `/health/liveliness` cannot respond → orchestrator healthcheck fails → container is SIGKILLed (exit 137) - all in-flight async I/O stalls, producing a burst of *misleading* secondary errors when the loop resumes: Redis read timeouts, `httpx.ConnectTimeout` to the **local*…