Toggle session panel with Escape as in-game pause overlay

- Panel shows in Main while disconnected, auto-hides once a connection is
  established, and toggles open/closed with Escape in the Lobby or on a Map.
- Escape now pauses gameplay (active mode exits, cursor freed, paint and
  movement disabled) instead of ending the match directly; closing restores
  the prior mode via SwitchTo.
- Disconnect button is context-aware: leaves the session in the Lobby, acts
  as "Back to Lobby" (EndMatch) for the match authority on a Map, and stays a
  plain disconnect for non-authority clients on a Map.
- Removed the Escape->EndMatch handler from MatchManager; match end now routes
  through RequestEndMatch with the same authority routing.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Assets/Scripts/OnlineSessionBrowserUI.cs

@@ -1,7 +1,11 @@
 using System.Collections.Generic;
 using TMPro;
 using UnityEngine;
+using UnityEngine.SceneManagement;
 using UnityEngine.UI;
+#if ENABLE_INPUT_SYSTEM
+using UnityEngine.InputSystem;
+#endif
 
 /// <summary>
 /// uGUI binding for <see cref="OnlineSessionManager"/>. Drives the server-browser canvas - Host / Refresh /
@@ -13,6 +17,13 @@ using UnityEngine.UI;
 /// Selection model: Refresh fills the list with clones of <see cref="entryTemplate"/> (each a clickable row
 /// showing name + player count). Clicking a row selects it; Join connects to the selected session. While
 /// connected, only Disconnect is interactable.
+///
+/// Overlay behaviour: the panel is always shown in Main (not connected). Once a connection is up it hides;
+/// in the lobby/map Esc toggles it back as a modal pause overlay (cursor freed, local gameplay suspended via
+/// <see cref="GameModeManager.SetPaused"/>). On the map the Disconnect button becomes "Back to Lobby" for the
+/// match authority (ends the match), while everyone else (in the lobby, or a non-authority client on the map)
+/// gets a plain disconnect. Only the visual <see cref="panelRoot"/> is toggled - this binder stays alive on
+/// its (always-active) canvas so it keeps reading Esc while the panel is hidden.
 /// </summary>
 public class OnlineSessionBrowserUI : MonoBehaviour
 {
@@ -33,6 +44,11 @@ public class OnlineSessionBrowserUI : MonoBehaviour
     [Header("Status")]
     [SerializeField] private TMP_Text statusLabel;
 
+    [Header("Overlay")]
+    [Tooltip("Visual container toggled by Esc while connected (the panel root). Must be a CHILD of this " +
+             "binder's object so the binder keeps running - and reading Esc - while the panel is hidden.")]
+    [SerializeField] private GameObject panelRoot;
+
     [Tooltip("Background tint of the selected row.")]
     [SerializeField] private Color selectedTint = new Color(0.26f, 0.52f, 0.96f, 1f);
     [Tooltip("Background tint of an unselected row.")]
@@ -42,10 +58,22 @@ public class OnlineSessionBrowserUI : MonoBehaviour
     private readonly List<Row> _rows = new List<Row>();
     private string _selectedId;
 
+    private MatchManager _match;          // local match state (scene kind + authority); found at runtime
+    private GameModeManager _gameMode;    // pause hook for the modal overlay; found at runtime
+    private TMP_Text _disconnectLabel;    // disconnect button caption (relabelled to "Back to Lobby")
+
+    private bool _open;                   // Esc-toggled visibility while connected
+    private bool _connected;              // last-seen connection state (to detect transitions)
+    private string _lastScene;            // last-seen active scene name (to auto-close on a scene change)
+    private string _disconnectText;       // last applied caption (avoids per-frame TMP churn)
+
     private void Awake()
     {
         // The template is the prototype, never shown itself - layout ignores it while disabled.
         if (entryTemplate) entryTemplate.SetActive(false);
+
+        _match = FindFirstObjectByType<MatchManager>();
+        _gameMode = FindFirstObjectByType<GameModeManager>();
     }
 
     private void OnEnable()
@@ -53,7 +81,11 @@ public class OnlineSessionBrowserUI : MonoBehaviour
         if (hostButton) hostButton.onClick.AddListener(OnHost);
         if (refreshButton) refreshButton.onClick.AddListener(OnRefresh);
         if (joinButton) joinButton.onClick.AddListener(OnJoin);
-        if (disconnectButton) disconnectButton.onClick.AddListener(OnDisconnect);
+        if (disconnectButton)
+        {
+            disconnectButton.onClick.AddListener(OnDisconnect);
+            _disconnectLabel = disconnectButton.GetComponentInChildren<TMP_Text>(true);
+        }
 
         if (manager)
         {
@@ -61,8 +93,10 @@ public class OnlineSessionBrowserUI : MonoBehaviour
             manager.SessionsChanged += RebuildList;
         }
 
+        _connected = manager && manager.IsConnected;
         RebuildList();
         OnManagerChanged();
+        ApplyVisibility();
     }
 
     private void OnDisable()
@@ -79,16 +113,92 @@ public class OnlineSessionBrowserUI : MonoBehaviour
         }
     }
 
+    private void Update()
+    {
+        if (!manager) return;
+        bool connected = manager.IsConnected;
+
+        // Auto-close the overlay if the scene changed underneath it (a remote ended/started the match, or
+        // we walked into Start Match) so it never lingers as a stale pause across a transition.
+        string scene = SceneManager.GetActiveScene().name;
+        if (connected && _open && _lastScene != null && scene != _lastScene)
+            SetOpen(false);
+        _lastScene = scene;
+
+        if (!connected) return;                                   // Main: panel always shown, Esc ignored
+
+        bool inLobbyOrMap = _match && (_match.IsLocalSceneLobby || _match.IsLocalSceneMap);
+        if (inLobbyOrMap && EscapePressed())
+            SetOpen(!_open);
+
+        RefreshDisconnectLabel();
+    }
+
     private void OnHost() { if (manager) manager.Host(); }
     private void OnRefresh() { if (manager) manager.Refresh(); }
     private void OnJoin() { if (manager && !string.IsNullOrEmpty(_selectedId)) manager.Join(_selectedId); }
-    private void OnDisconnect() { if (manager) manager.Disconnect(); }
+
+    private void OnDisconnect()
+    {
+        if (!manager) return;
+
+        // On the map, the match AUTHORITY's button means "Back to Lobby" (end the match for everyone)
+        // rather than leaving the session. Everyone else - in the lobby, or a non-authority client on the
+        // map - does a plain disconnect.
+        if (_match && _match.IsLocalSceneMap && _match.IsLocalMatchAuthority)
+        {
+            _match.RequestEndMatch();
+            SetOpen(false);            // heading back to the lobby; close the overlay + resume input
+            return;
+        }
+
+        manager.Disconnect();
+    }
 
     private void OnManagerChanged()
     {
         if (!manager) return;
+
+        bool connected = manager.IsConnected;
+        if (connected != _connected)
+        {
+            _connected = connected;
+            // Connection up (hosted/joined) -> hide the panel; Esc reopens it in the lobby/map.
+            // Back to Main (disconnect/shutdown) -> show it again and drop any pause.
+            _open = false;
+            if (!connected && _gameMode) _gameMode.SetPaused(false);
+            ApplyVisibility();
+        }
+
         if (statusLabel) statusLabel.text = manager.Status;
         UpdateButtons();
+        RefreshDisconnectLabel();
+    }
+
+    private void SetOpen(bool open)
+    {
+        _open = open;
+        ApplyVisibility();
+        if (_gameMode) _gameMode.SetPaused(open);
+    }
+
+    private void ApplyVisibility()
+    {
+        bool show = !(manager && manager.IsConnected) || _open;
+        if (panelRoot && panelRoot.activeSelf != show)
+            panelRoot.SetActive(show);
+    }
+
+    private void RefreshDisconnectLabel()
+    {
+        if (!_disconnectLabel) return;
+        bool backToLobby = _match && _match.IsLocalSceneMap && _match.IsLocalMatchAuthority;
+        string text = backToLobby ? "Back to Lobby" : "Disconnect";
+        if (text != _disconnectText)
+        {
+            _disconnectText = text;
+            _disconnectLabel.text = text;
+        }
     }
 
     private void UpdateButtons()
@@ -165,4 +275,13 @@ public class OnlineSessionBrowserUI : MonoBehaviour
         var t = root.Find(childName);
         return t ? t.GetComponent<TMP_Text>() : null;
     }
+
+    private static bool EscapePressed()
+    {
+#if ENABLE_INPUT_SYSTEM
+        return Keyboard.current != null && Keyboard.current.escapeKey.wasPressedThisFrame;
+#else
+        return Input.GetKeyDown(KeyCode.Escape);
+#endif
+    }
 }