v1.9.0

Added — TUI as the default entry + full control center

nightshift ui is now the front door and a complete control center — you no
longer need an already-running run to open it, and every CLI subcommand is
reachable from inside the TUI.

• Bare nightshift launches the TUI in a terminal (the default experience).
  Piped / non-interactive invocations and nightshift help still print help, so
  scripting is unchanged. All subcommands behave exactly as before.
• Home / launcher state when no run is live: project status, last-run
  summary, the detected todo/plan files (with task counts), and actions —
  Start · Init · Review · Resume · command palette · Quit.
• Command palette (:) runs every subcommand from inside the TUI
  (start · stop · status · review · resume · init · bulletproof · version).
  Output-producing commands render in a scrollable modal; start launches the
  run detached and the view flips to live automatically.
• Thin orchestration, no reimplementation. The TUI spawns the real
  bin/nightshift subcommands (passed in via NIGHTSHIFT_BIN); the bash
  runners and their logic are untouched.
• The live monitor/steer view (tasks, log, pause/resume/skip/stop/message) is
  unchanged; the UI now switches home↔live automatically as runs start and end.
• Bash fallback stays monitor-only; the launcher is the Node UI (Node 22+).