v1.24.0 — aichat move-account, and rewind for ported Codex sessions

New: aichat move-account (PR [#159])

Move a Claude or Codex session between account config dirs — e.g. a personal ~/.codex and a work ~/.codex-rja (selected via CLAUDE_CONFIG_DIR / CODEX_HOME) — for sessions started under the wrong account. The session stays in the same project; nothing in the transcript is rewritten.

• Resolve by UUID (full or partial), Claude session name, or Codex thread name; matching is case-insensitive, an exact name outranks a UUID prefix, and ambiguity is refused, not guessed. Without --from, all local homes (~/.claude* / ~/.codex*) are searched.
• Claude moves carry the sidecar dir (subagents, tool-results, workflows); Codex moves carry the session's thread-name entries in session_index.jsonl (atomic rewrite, trailing-newline guard).
• The copy is size-verified — including a source re-check that catches a still-running session — before the source is deleted; --keep copies instead of moving.
• Prints a paste-ready, shell-quoted resume command naming the target account explicitly.

Docs: the "Move Account" page under aichat in the Starlight site. Details: release-notes/pr-159-aichat-move-account.md.

Fix: ported Codex sessions can rewind (PR [#158])

After aichat port from Claude to Codex, the conversation continued fine but rewind did nothing: the porter synthesized only the response_item stream the model reads, omitting the event_msg UI event log the Codex TUI replays for scrollback and rewind points. The porter now emits the event stream too (one user_message event per user turn, agent_message per assistant turn), so ported sessions rewind like native ones.