Treat inference hook denials as terminal errors (#60511)

## Why

An explicit denial from a workspace inference hook should stop the request, including retries and compaction model fallback.

## What changed

Recognize `inference_hook_denied` provider errors and preserve the provider's message, with a fallback when none is supplied. Expose the distinct `inferenceHookDenied` error through the app-server protocol and generated schemas and SDK types. Treat the denial as non-retryable during turns, compaction, and guardian review.

## Testing

Add coverage for terminal denials over HTTP, SSE, and WebSocket, error serialization and persistence in `thread/read`, and compaction failures that preserve token usage and history without retrying or falling back to another model.

GitOrigin-RevId: 2ebd480f01e52f4e6bd3db8a0f92d5814d18ccb1

codex-rs/codex-api/src/sse/responses.rs

@@ -683,6 +683,7 @@ async fn process_sse_with_treatment(
                         | ApiError::ContextWindowExceeded
                         | ApiError::InvalidRequest { .. }
                         | ApiError::SessionBudgetExceeded
+                        | ApiError::InferenceHookDenied { .. }
                         | ApiError::AccessProgramNotEnabled { .. }
                         | ApiError::ContentPolicyViolation { .. }
                         | ApiError::ResponseIncomplete(_)

codex-rs/codex-api/src/sse/responses_error_tests.rs

@@ -115,6 +115,7 @@ async fn terminal_failure_with_retry_header_ends_stream_immediately() {
     for (code, expected) in [
         ("flex_unavailable", CodexErrorInfo::FlexUnavailable),
         ("budget_reached", CodexErrorInfo::SessionBudgetExceeded),
+        ("inference_hook_denied", CodexErrorInfo::InferenceHookDenied),
         (
             "context_length_exceeded",
             CodexErrorInfo::ContextWindowExceeded,