Preserve bio policy errors as a distinct non-retryable error (#46306)

## Why

Streaming `bio_policy` failures were classified as generic invalid requests, losing their policy-specific classification.

## What changed

- Add `BioPolicy` errors across the API and core protocol, recognizing streaming failures and HTTP 400 responses, including wrapped WebSocket errors.
- Preserve server messages and use a biological-risk fallback when the message is missing or blank.
- Treat bio policy errors as non-retryable in core and guardian handling, and classify them in diagnostics and telemetry.
- Map `BioPolicy` to `other` in the app-server v2 protocol.

## Testing

Add coverage for error classification, message preservation and fallbacks, HTTP and wrapped WebSocket responses, guardian retry decisions, and app-server conversion. Extend the core integration test to verify that bio policy failures emit a typed error and complete the turn after a single request.

GitOrigin-RevId: 78c2647e8fc8f80297cb8a23fff06ab141099632

codex-rs/app-server-protocol/src/protocol/v2/shared.rs

@@ -129,6 +129,7 @@ impl From<CoreCodexErrorInfo> for CodexErrorInfo {
             CoreCodexErrorInfo::RateLimitExceeded => CodexErrorInfo::RateLimitExceeded,
             CoreCodexErrorInfo::ServerOverloaded => CodexErrorInfo::ServerOverloaded,
             CoreCodexErrorInfo::CyberPolicy => CodexErrorInfo::CyberPolicy,
+            CoreCodexErrorInfo::BioPolicy => CodexErrorInfo::Other,
             CoreCodexErrorInfo::MisalignmentPolicyViolation => {
                 CodexErrorInfo::MisalignmentPolicyViolation
             }

codex-rs/app-server-protocol/src/protocol/v2/tests.rs

@@ -4671,6 +4671,7 @@ fn codex_error_info_serializes_http_status_code_in_camel_case() {
 fn core_error_info_converts_to_camel_case() {
     for (core, expected) in [
         (CoreCodexErrorInfo::CyberPolicy, json!("cyberPolicy")),
+        (CoreCodexErrorInfo::BioPolicy, json!("other")),
         (
             CoreCodexErrorInfo::RateLimitExceeded,
             json!("rateLimitExceeded"),