v5.9.0

Claude Desktop deployment completion (RDR-126): the .mcpb Desktop Extension
substrate already shipped; this release adds the remaining first-run and
lifecycle surface so a Desktop-only user gets a working, removable daemon
without touching a terminal.

Added

• First-run banner (RDR-126 §3). On the first MCP startup the server
  announces that the background T2 daemon was installed (or was already
  configured) and how to remove it in-chat, delivered by prepending to the
  first tool response. One-shot, gated by a marker that is written only after
  the banner is actually delivered (a failed delivery retries on the next tool
  call rather than burning the one-shot).
• daemon_uninstall MCP tool (RDR-126 §4), on nx-mcp. In-chat removal of
  the first-run daemon. confirm=false (default) is a dry run that describes
  what would be removed; confirm=true removes the OS autostart unit, stops
  the daemon, and clears the first-run marker; remove_data=true additionally
  wipes the nexus config directory (guarded against shallow/unsafe paths).

Changed

• T2 autostart install/uninstall lifted into nexus.daemon.installer
  (RDR-126 §2). The OS-unit logic moved out of the Click command bodies into
  pure library functions returning structured results; nx daemon t2 install/uninstall and the MCP first-run path now call it in-process. No
  user-facing CLI behavior change.

CI/release

• mcpb version-sync guard (RDR-126 §7). release.yml now fails the publish
  if mcpb/manifest.json's version does not match the release tag, closing the
  third version-drift surface (the Desktop Extension) at publish time.