set process/thread titles for decky and plugins

sadly requires the `setproctitle` pypi module because python doesn't have a builtin to do this :/

backend/decky_loader/plugin/sandboxed_plugin.py

@@ -7,6 +7,7 @@ from sys import exit, path as syspath, modules as sysmodules
 from traceback import format_exc
 from asyncio import (get_event_loop, new_event_loop,
                      set_event_loop, sleep)
+from setproctitle import setproctitle, setthreadtitle
 
 from .messages import SocketResponseDict, SocketMessageType
 from ..localplatform.localsocket import LocalSocket
@@ -48,6 +49,9 @@ class SandboxedPlugin:
             signal(SIGINT, SIG_IGN)
             signal(SIGTERM, SIG_IGN)
 
+            setproctitle(f"{self.name} ({self.file})")
+            setthreadtitle(self.name)
+
             set_event_loop(new_event_loop())
             if self.passive:
                 return