Citation formatter: ``apply_inline_hyperlinks`` (the fallback path that chat-mode answers always hit because the langgraph-agent synthesis doesn't emit a ``## Sources`` block in its prose) now dispatches on ``CitationFormatter.mode`` instead of hard-coding ``NUMBER_HYPERLINKS``. The user's ``report.citation_format`` setting is now honored for chat-mode citations — picking "Domain ID Hyperlinks" or "Source-Tagged Hyperlinks" actually produces ``[[arxiv.org-1]](url)`` / ``[[arxiv-1]](url)`` instead of every chat answer coming out as ``[[1]](url)``.
