Surface misalignment policy violations as typed errors (#38682)

## What changed

- Recognize `misalignment_policy_violation` errors from response streams and HTTP 400 or 403 responses.
- Preserve the upstream message, use a fallback for blank messages, and treat the error as non-retryable.
- Expose `misalignmentPolicyViolation` through the app-server protocol and generated schemas so turns fail with a typed terminal error.

## Testing

- Cover streamed and HTTP policy violations, fallback messages, retry behavior, and app-server turn completion.

GitOrigin-RevId: fd3485bf0be7bfe3d51c078bbc36a081692fd57f

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

@@ -80,6 +80,7 @@ pub enum CodexErrorInfo {
     UsageLimitExceeded,
     ServerOverloaded,
     CyberPolicy,
+    MisalignmentPolicyViolation,
     HttpConnectionFailed {
         #[serde(rename = "httpStatusCode")]
         #[ts(rename = "httpStatusCode")]
@@ -126,6 +127,9 @@ impl From<CoreCodexErrorInfo> for CodexErrorInfo {
             CoreCodexErrorInfo::UsageLimitExceeded => CodexErrorInfo::UsageLimitExceeded,
             CoreCodexErrorInfo::ServerOverloaded => CodexErrorInfo::ServerOverloaded,
             CoreCodexErrorInfo::CyberPolicy => CodexErrorInfo::CyberPolicy,
+            CoreCodexErrorInfo::MisalignmentPolicyViolation => {
+                CodexErrorInfo::MisalignmentPolicyViolation
+            }
             CoreCodexErrorInfo::HttpConnectionFailed { http_status_code } => {
                 CodexErrorInfo::HttpConnectionFailed { http_status_code }
             }