Function accumulate_and_translate 

fn accumulate_and_translate(
    broker: &Broker,
    block_id: &str,
    line_buf: &mut Vec<u8>,
    chunk: &[u8],
    translator: &mut ClaudeTranslator,
)

Publish the events extract_agent_events produced on the WPS scope agent_event:<block_id>. Phase 1.5 PR 1 hook for agent panes. Called only when is_agent is true at spawn time (see read-task closure in start()).