## Why
Responses overload and exhausted-request errors could terminate despite server retry advice, and WebSocket-to-HTTP fallback could issue a request before the advised deadline.
## What changed
- Allow `ServerOverloaded` and `RetryLimit` errors to retry when server advice is present, within the configured retry budgets.
- Preserve `Retry-After` headers from rejected WebSocket upgrades and wait for the server deadline before falling back to HTTP.
- Keep quota, usage-limit, and policy failures terminal even when they include retry advice.
## Testing
Add coverage for HTTP overload and rate-limit recovery, WebSocket upgrade rejection and fallback timing, retry deadline preservation through error mapping, and retry limits for sampling and manual and automatic compaction.
GitOrigin-RevId: 72d30a9f078652664754dfa971fd7dc7a78f20e8