feat: Windows daemon lifecycle (W3) — Startup-folder autostart

The Linux node runs under `systemctl --user`. Windows has no per-user
equivalent that works without elevation: `schtasks /create /sc ONLOGON`
(even `/rl LIMITED /it`) fails with "Access is denied" for a non-admin
user, because a logon trigger touches machine-wide scheduler state.

So autostart is a `.vbs` in the per-user Startup folder instead:

    CreateObject("WScript.Shell").Run Chr(34) & "<exe>" & Chr(34), 0, False

wscript runs it at every sign-in, hidden (0) and non-blocking. No admin,
no console window, no new dependency. Verified end to end: the launcher
brings the daemon up with no window and it answers its loopback API.

node/platform.py
  autostart_install/remove/status  — write / delete / detect the launcher
  autostart_run/end                — start now (DETACHED|NO_WINDOW) / taskkill
  _node_exe                        — PATH, then next to sys.executable, then argv[0]

node/daemon.py
  new `autostart install|remove|start|stop|status` verb
  reload (win32)         -> POST /api/reload on the loopback API
  restart-daemon (win32) -> autostart_end + autostart_run
  reset (win32)          -> also removes the launcher

client/main.js, preload.js
  node:autostart handler + winAutostart* helpers (kept in step with platform.py)
  node:service-status (win32) probes the daemon; stop/restart/start use
  taskkill + a detached, windowless spawn

Tests: 8 autostart cases in test_platform.py (mocked sys.platform, APPDATA
pointed at tmp); `autostart status` added to the CLI dispatch sweep. Full
meshbay-node suite green on Windows (784 passed / 34 skipped).

Still open: no CTRL_CLOSE_EVENT handler, so a bare taskkill / window close
does not run _shutdown() (SetConsoleCtrlHandler, follow-up). Service mode
(pywin32/NSSM) stays Phase 2.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

2 files changed, 155 insertions, 12 deletions

diff --git a/packages/meshbay-node/src/meshbay_node/daemon.py b/packages/meshbay-node/src/meshbay_node/daemon.py
index 5aa6654..b5a249d 100644
--- a/packages/meshbay-node/src/meshbay_node/daemon.py
+++ b/packages/meshbay-node/src/meshbay_node/daemon.py
@@ -1643,7 +1643,8 @@ def main() -> None:
                         choices=["init", "reset", "status", "gek-init",
                                  "gek", "operator", "member", "group", "file",
                                  "video", "denylist", "stun", "reload",
-                                 "restart-daemon", "calibrate-argon2"],
+                                 "restart-daemon", "autostart",
+                                 "calibrate-argon2"],
                         help="init: provision config + keystore | reset: erase all "
                              "node state | status: node state and keys "
                              "| operator pair: pair a "
@@ -1652,15 +1653,18 @@ def main() -> None:
                              "| video rematch: re-resolve TMDB matches for a group's "
                              "videos | denylist show|clear "
                              "| stun list|add|remove|reset "
-                             "| reload: re-read node.toml "
-                             "(systemctl --user reload) | restart-daemon: restart "
-                             "the systemd unit (systemctl --user restart) "
+                             "| reload: re-read node.toml (hot; systemd or the "
+                             "loopback API) | restart-daemon: restart the node "
+                             "(systemd unit, or the Windows autostart launcher) "
+                             "| autostart install|remove|start|stop|status "
+                             "(Windows: run meshbay-node at each sign-in) "
                              "| calibrate-argon2: benchmark")
     parser.add_argument("subcommand", nargs="?",
                         help="'pair' for operator; list|invite|revoke|unpin for "
                              "member; list|add|remove for group; init|rotate for gek; "
                              "list|rm for file; rematch for video; show|clear for "
-                             "denylist; list|add|remove|reset for stun")
+                             "denylist; list|add|remove|reset for stun; "
+                             "install|remove|start|stop|status for autostart")
     parser.add_argument("target", nargs="?",
                         help="username for member invite|revoke|unpin; group name "
                              "for group add; file id for file rm; identifier for "
@@ -1771,7 +1775,8 @@ def main() -> None:
         print("Next steps:")
         print(f"  1. Link this node key on {hub_url} → Settings → Link Node")
         if sys.platform == "win32":
-            print("  2. meshbay-node  (start the daemon)")
+            print("  2. meshbay-node autostart install   (run at each sign-in)")
+            print("     — or just: meshbay-node          (start it now, this session)")
         else:
             print("  2. systemctl --user enable --now meshbay-node")
         print("  3. meshbay-node group add <name> --dir /path/to/files")
@@ -1828,7 +1833,10 @@ def main() -> None:
             except Exception:
                 print("Could not unlink from hub (daemon not reachable).")
 
-        if sys.platform != "win32":
+        if sys.platform == "win32":
+            from meshbay_node.platform import autostart_remove
+            autostart_remove()
+        else:
             _sp.run(["systemctl", "--user", "disable", "--now", "meshbay-node"],
                     capture_output=True)
 
@@ -2072,8 +2080,12 @@ def main() -> None:
 
     if args.command == "reload":
         if sys.platform == "win32":
-            print("reload is not supported on Windows — restart the daemon instead.")
-            sys.exit(1)
+            # No systemd, no SIGHUP: the daemon exposes a hot reload on its
+            # own loopback API (the same one ops.reload_config drives).
+            cfg = load_config(args.config or DEFAULT_CONFIG_PATH)
+            _daemon_api(cfg, "/api/reload", method="POST")
+            print("sent reload to the running node")
+            return
         _systemctl_user(
             "reload", "meshbay-node",
             not_running_hint="Node is not running as a systemd unit — start it "
@@ -2084,9 +2096,16 @@ def main() -> None:
 
     if args.command == "restart-daemon":
         if sys.platform == "win32":
-            print("restart-daemon is not supported on Windows — stop and start "
-                  "the daemon manually.")
-            sys.exit(1)
+            from meshbay_node.platform import autostart_end, autostart_run
+            autostart_end()   # kill whatever is running now
+            try:
+                autostart_run()
+            except RuntimeError as e:
+                print(f"Could not restart: {e}. Stop the daemon (Ctrl+C) and "
+                      "relaunch it from where meshbay-node is on PATH.")
+                sys.exit(1)
+            print("restarted the node")
+            return
         _systemctl_user(
             "restart", "meshbay-node",
             not_running_hint="meshbay-node is not installed as a systemd unit — "
@@ -2096,6 +2115,42 @@ def main() -> None:
                   "watch logs:    journalctl --user -u meshbay-node -f")
         return
 
+    if args.command == "autostart":
+        from meshbay_node import platform as _plat
+        if sys.platform != "win32":
+            print("autostart is Windows-only — elsewhere use "
+                  "'systemctl --user enable --now meshbay-node'.")
+            sys.exit(1)
+        sub = args.subcommand or "status"
+        if sub == "install":
+            _plat.autostart_install()
+            print("Installed the Startup launcher — meshbay-node starts at "
+                  "each sign-in (no window, no admin).")
+            print("Start it now with: meshbay-node autostart start")
+        elif sub == "remove":
+            _plat.autostart_remove()
+            print("Removed the Startup launcher.")
+        elif sub == "start":
+            try:
+                _plat.autostart_run()
+            except RuntimeError as e:
+                print(f"Could not start: {e}")
+                sys.exit(1)
+            print("started")
+        elif sub == "stop":
+            _plat.autostart_end()
+            print("stopped")
+        elif sub == "status":
+            st = _plat.autostart_status()
+            if st["installed"]:
+                print("autostart    installed — runs meshbay-node at sign-in")
+            else:
+                print("autostart    not installed — meshbay-node autostart install")
+        else:
+            print("autostart: install | remove | start | stop | status")
+            sys.exit(1)
+        return
+
     if args.command == "denylist":
         cfg = load_config(args.config or DEFAULT_CONFIG_PATH)
         sub = args.subcommand or "show"
diff --git a/packages/meshbay-node/src/meshbay_node/platform.py b/packages/meshbay-node/src/meshbay_node/platform.py
index 351289f..b59418f 100644
--- a/packages/meshbay-node/src/meshbay_node/platform.py
+++ b/packages/meshbay-node/src/meshbay_node/platform.py
@@ -3,6 +3,7 @@
 import asyncio
 import os
 import shutil
+import subprocess
 import sys
 from pathlib import Path
 
@@ -109,3 +110,90 @@ def ffmpeg_cmd() -> str:
 
 def ffprobe_cmd() -> str:
     return _ffprobe_path
+
+
+# ── Autostart (Windows) ──────────────────────────────────────────────────────
+#
+# The Windows stand-in for the Linux `systemctl --user` unit. Task Scheduler
+# would be nicer (retry semantics), but a logon-triggered task needs elevation
+# to create — and this must work for an ordinary user with no admin rights.
+# So: a `.vbs` launcher in the per-user Startup folder. wscript runs it hidden
+# (Run(..., 0, ...)) at every sign-in; no console window, no admin, no
+# third-party dependency.
+
+TASK_NAME = "MeshBay Node"   # the name the Electron client shows
+
+
+def autostart_supported() -> bool:
+    return sys.platform == "win32"
+
+
+def _startup_vbs() -> Path:
+    base = os.environ.get("APPDATA") or str(Path.home() / "AppData" / "Roaming")
+    return (Path(base) / "Microsoft" / "Windows" / "Start Menu" / "Programs"
+            / "Startup" / "MeshBay Node.vbs")
+
+
+def _node_exe() -> str | None:
+    """Best guess at the meshbay-node launcher: PATH first, then next to the
+    interpreter (a venv's Scripts/ dir, or a bundled runtime), then argv[0]."""
+    found = shutil.which("meshbay-node")
+    if found:
+        return found
+    for cand in (Path(sys.executable).parent / "meshbay-node.exe",
+                 Path(sys.argv[0])):
+        if cand.name.lower().startswith("meshbay-node") and cand.exists():
+            return str(cand.resolve())
+    return None
+
+
+def autostart_status() -> dict:
+    """{'installed': bool, 'state': str}. 'state' is left empty — there is no
+    Task Scheduler to ask 'is it running'; the Node page probes the daemon."""
+    if not autostart_supported():
+        return {"installed": False, "state": ""}
+    return {"installed": _startup_vbs().exists(), "state": ""}
+
+
+def autostart_install(exe: str | None = None) -> None:
+    """Write the Startup-folder launcher. Raises RuntimeError on failure."""
+    if not autostart_supported():
+        raise RuntimeError("autostart is Windows-only")
+    exe = exe or _node_exe()
+    if not exe:
+        raise RuntimeError(
+            "cannot locate the meshbay-node launcher — pass its path, or run "
+            "this from where meshbay-node is on PATH")
+    vbs = _startup_vbs()
+    vbs.parent.mkdir(parents=True, exist_ok=True)
+    # Chr(34) is a literal " — wraps the path so a space in it doesn't split the
+    # command. 0 = hidden window, False = don't wait. (A Windows path cannot
+    # itself contain ", so no further escaping is needed.)
+    vbs.write_text(
+        f'CreateObject("WScript.Shell").Run Chr(34) & "{exe}" & Chr(34), 0, False\n',
+        encoding="utf-8", newline="\r\n")
+
+
+def autostart_remove() -> None:
+    """Delete the Startup-folder launcher if present."""
+    if autostart_supported():
+        _startup_vbs().unlink(missing_ok=True)
+
+
+def autostart_run() -> None:
+    """Start the daemon now, detached and windowless. Raises RuntimeError if
+    the launcher cannot be located."""
+    if not autostart_supported():
+        raise RuntimeError("autostart is Windows-only")
+    exe = _node_exe()
+    if not exe:
+        raise RuntimeError("cannot locate the meshbay-node launcher")
+    subprocess.Popen([exe], creationflags=0x00000008 | 0x08000000,  # DETACHED | NO_WINDOW
+                     close_fds=True)
+
+
+def autostart_end() -> None:
+    """Stop any running daemon (hard: there is no CTRL_CLOSE handler yet)."""
+    if autostart_supported():
+        subprocess.run(["taskkill", "/IM", "meshbay-node.exe", "/F"],
+                       capture_output=True)