Publish Raw SDK Event

Publish a raw SDK event for transformation and streaming.

This endpoint replaces the deprecated `/stream-events` endpoint.
Events are transformed via SDK-specific adapters (based on `sdk_type` and `sdk_version`)
and the resulting stream parts are published to Redis for real-time consumption.

Messages that should be stored (e.g., AssistantMessage, UserMessage) are
automatically persisted to MongoDB for later retrieval.

**Supported SDK Types:**
- `claude`: Claude Agent SDK messages (StreamEvent, AssistantMessage, etc.)
- `codex`: Codex SDK thread events (`item.*`, `turn.*`, `thread.*`)
- `terminal_use`: Direct UIMessage format (Vercel-compatible)

**What gets stored:**
- AssistantMessage, UserMessage, ResultMessage, SystemMessage

**What does NOT get stored:**
- StreamEvent (ephemeral streaming deltas)

Requires `update` permission on the task.