fix(desktop): keep named-profile desktop backends per-profile (#44510)

Desktop spawns its dashboard backend with `--profile <name>` and
`HERMES_DESKTOP=1`. cmd_dashboard's unified-launch routing treats any
named profile as a request for the shared machine dashboard: it re-execs
as the default profile (dropping HERMES_HOME) or, when one is already
listening, prints "Machine dashboard already running ... Managing profile
'<name>'" and exits 0. Either way the desktop-spawned child exits before
the app sees a ready backend, so Desktop retries forever — the Windows
named-profile boot loop in the post-mortem.

Skip the machine-dashboard reroute when HERMES_DESKTOP=1 so desktop pool
backends stay per-profile (which is what the pool expects). Carved out of
#44478.

Co-authored-by: AJ <yspdev@gmail.com>

hermes_cli/main.py

@@ -10332,6 +10332,8 @@ def cmd_dashboard(args):
         _launch_profile not in ("default", "custom")
         and not getattr(args, "isolated", False)
         and not getattr(args, "open_profile", "")
+        # Desktop pool backends are intentionally per-profile.
+        and os.environ.get("HERMES_DESKTOP") != "1"
     ):
         url = f"http://{args.host or '127.0.0.1'}:{args.port}/?profile={_launch_profile}"
         if _dashboard_listening(args.host, args.port):