- Handle apply_patch custom tool call streaming deltas and snapshots for Responses API translation
- Track and resolve step indexes, function call identities, and error states across stream events
- Propagate apply_patch tool input errors and upstream failure states in stream and non-stream responses
- Add `WriteModelListResponse` to `BaseAPIHandler` to apply plugin interceptors and record request lifecycles for model catalog responses.
- Update OpenAI, Claude, Gemini, Grok, and Codex model listing endpoints to route responses through the unified interceptor helper.
Closes: #5742