Background services without systemd (runit, OpenRC, ...)

Co-Authored-By: Claude Opus 5.5 <[email protected]>

Core.py

@@ -13,6 +13,7 @@ picked for one Sara program looks the same in all of them.
 """
 
 import os
+import shutil
 import sys
 from dataclasses import asdict, dataclass, field
 from pathlib import Path
@@ -64,7 +65,14 @@ ReceiptsDir = DataDir / "Receipts"  # what each install placed, for exact remova
 PristineDir = DataDir / "Pristine"  # the default configs as last installed (merge base)
 BackupsDir = DataDir / "Backups"  # displaced files and pre-merge config copies
 DownloadsDir = CacheHome / "SaraSuite" / "Downloads"  # extracted source archives
-ServicesDir = DataDir / "Services"  # Windows: <Name>.pid of each running background service
+# <Name>.pid and <Name>.log of each service SaraSuite runs itself (Services.py).
+ServicesDir = DataDir / "Services"
+
+# Linux: whether systemd runs the system, and so --user services. Without it
+# (runit on Void, OpenRC, s6, dinit, ...) services run the way they do on
+# Windows (Services.py), started at login from AutostartDir.
+HasSystemd = not IsWindows and Path("/run/systemd/system").is_dir() and shutil.which("systemctl") is not None
+AutostartDir = ConfigHome / "autostart"
 
 # Bundled read-only files (program manifests, fonts). Inside a PyInstaller
 # build they're unpacked to sys._MEIPASS rather than next to the code.