Claude adapter emits only init events when Claude SDK streams stream_event envelopes

[tmsdnl]

With @anthropic-ai/claude-agent-sdk 0.1.46/0.1.47, the SDK streams items as { type: "stream_event", event: {...}, session_id }. The adapter’s normalizeClaudeStreamMessage only inspects the top-level type and short-circuits to init when session_id is present. Result: every chunk becomes init; no message/tool_use/usage/done events are emitted, so assistant text is never captured.

Reproduce

1. Use runStreamed with streamPartialMessages: true.
2. Log events: init only entries with originalItem.type === "stream_event" (e.g., content_block_delta/text_delta), but no message/done.
3. Final review buffer stays empty ([no assistant response captured]).

Expected mapping

• Unwrap stream_event.event, keep session_id.
• content_block_delta/text_delta → message (delta: true).
• content_block_start tool_use → tool_use.
• message_delta usage → usage; message_stop → done.
• Only actual system/sdk init should map to init.

Versions

• @headless-coder-sdk/claude-adapter: 0.22.0
• @headless-coder-sdk/core: 0.22.0
• @anthropic-ai/claude-agent-sdk: 0.1.46, 0.1.47
• Node: 18+/25, macOS

Fix suggestion
Update normalizeClaudeStreamMessage to unwrap stream_event, handle content_block_*/message_delta/message_stop, and stop treating the mere presence of session_id as init.