v4.24.0 — scope the [CD] statusline badge to this session

Changed

• The [CD] statusline now shows only workers spawned by the current Claude Code session.
  When stdin contains Claude Code's snake_case session_id, the fragment requires a matching
  meta.json parentSessionId in addition to the existing running state and 90-second
  status.json freshness check. It groups live workers in fixed ds, ag, cx, oc, cp
  order (for example, [CD](ds:1,ag:2,cx:1)), accepts both long and short backend spellings,
  and excludes workers from other parent sessions plus legacy workers without parent metadata.
  The group uses the existing yellow counter color; [CD] remains cyan. Stdin is still drained
  fully, and callers without a non-empty session_id retain the global ▶N behavior unchanged.
  The hot path reads only status.json and meta.json, never transcripts.