Write mcp-loose-ends/matrix.json on invite arrival (before wake) and
after join_room clears an invite. The harness scans mcp-loose-ends/
generically in get_loose_ends, so pending invites are visible there
without any harness-side changes.
- paths: add mcp_loose_ends_dir() (mirrors hive-bash-mcp pattern)
- handlers: add refresh_invite_loose_ends() — atomic tmp+rename write
- handlers: join_room calls refresh after successful join to clear entry
- timeline: install_invite_handler refreshes loose-ends before wake
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