Admin: install parts, set time and weather; join without prompt

- VEHICLE: INSTALL for parts that are not installed - runs the game's own
  assembly (trigger "Assembly" like on load), so the part sits exactly on its
  pivot; synced to other players via FsmSync (MSCO_INSTALL)
- WORLD: time buttons (2-hour steps via the sun FSM's load path) and
  CLEAR / RAIN / THUNDERSTORM (weather front moved above the admin);
  sent to everyone as mod message "msco.world" (no server update needed)
- JOIN from the server browser/website connects right away in the main menu;
  server mods still ask before downloading

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

MultiplayerManager.cs

@@ -575,6 +575,19 @@ namespace MSCO
             if (CanCheat) AnnounceCheat(what);
         }
 
+        /// <summary>Admin: Uhrzeit (kind 1, Stunde) oder Wetter (kind 2: 0 klar, 1 Regen, 2 Gewitter) für alle umstellen.</summary>
+        public void WorldCheat(byte kind, int value)
+        {
+            if (!CanCheat) return;
+            Vector3 pos = localPlayer != null ? localPlayer.position : Vector3.zero;
+            string error = WorldAdmin.Apply(kind, value, pos);
+            if (error != null) { overlays.Log(error); return; }
+            SendModMessage(WorldAdmin.MessageId, WorldAdmin.Build(kind, value, pos));
+            AnnounceCheat(kind == WorldAdmin.KindHour
+                ? "set the time to " + value.ToString("00") + ":00"
+                : "set the weather to " + WorldAdmin.WeatherNames[value]);
+        }
+
         void AnnounceCheat(string what)
         {
             string text = OwnName() + " " + what + " (admin)";
@@ -642,7 +655,7 @@ namespace MSCO
             PendingJoinHost = host;
             PendingJoinPort = port;
             if (IsInSession || !MenuHelper.InMenu)
-                toasts.Add("Join link: " + host + ":" + port, "leave this game - then confirm JOIN in the main menu", UiTheme.Accent);
+                toasts.Add("Join link: " + host + ":" + port, "leave this game - you join automatically in the main menu", UiTheme.Accent);
         }
 
         public void CancelPendingJoin()
@@ -1010,6 +1023,10 @@ namespace MSCO
         {
             CheckHitch();
             CheckJoinRequest();
+            // JOIN im Server-Browser (Launcher/Website): ohne Rückfrage verbinden, sobald das Hauptmenü steht.
+            // Server-Mods fragen weiterhin extra nach (das sind Programme).
+            if (PendingJoinHost != null && !IsInSession && !checkingServer && MenuHelper.InMenu && Time.timeSinceLevelLoad > 1f)
+                ConfirmPendingJoin();
             MeasureFps();
             // Menü-Buttons des Spiels nicht durch unser Fenster hindurch auslösen (z.B. Changelog)
             // Solange das Multiplayer-Fenster offen ist, reagiert das Spielmenü (CONTINUE, QUIT ...) gar nicht;
@@ -1714,6 +1731,7 @@ namespace MSCO
                 string modId = r.ReadString();
                 int len = r.ReadInt32();
                 if (len < 0 || len > MaxModMessageBytes) return;
+                if (modId == WorldAdmin.MessageId) { WorldAdmin.Receive(r.ReadBytes(len)); return; } // Admin: Uhrzeit/Wetter
                 ModLoader.Message(modId, from, r.ReadBytes(len));
                 return;
             }