feat: Remote-Verbindungen – Windows-Workstations per WebSocket steuern

- RemoteConnectionManager: Singleton-Service verwaltet WebSocket-Verbindungen
  mit Command-Execution (Send/Receive mit Timeout + SemaphoreSlim-Locking)
- RemoteEndpoint: WebSocket-Endpoint /api/remote (auth-frei), REST-APIs für
  Connections/Assign/Unassign, PowerShell-Script-Auslieferung mit dynamischer URL
- remote.ps1: PowerShell-Client für Windows – verbindet per WebSocket,
  sendet Hostname/User/OS, empfängt und führt Befehle aus, Heartbeat
- remote_execute Tool: Neues Agent-Tool, nur verfügbar wenn Session eine
  zugeordnete Remote-Verbindung hat, führt PowerShell-Befehle remote aus
- Frontend: Menüpunkt 'Remote-Verbindungen' im Chat-Dropdown, Modal zeigt
  alle aktiven WebSocket-Verbindungen (Hostname, User, OS, Verbindungszeit),
  Verbinden/Trennen-Buttons pro Verbindung und Session
- Auth: /api/remote und /remote.ps1 von Authentifizierung ausgenommen

Architektur: Windows-Client → WebSocket → GOTT-Server → Agent-Tool
Session-gebunden: Eine Verbindung wird einer Session zugeordnet

wwwroot/js/modals.js

@@ -292,6 +292,104 @@ async function showOpenClawImportModal(sessionId) {
   }
 }
 
+// ── Remote-Verbindungen Modal ──
+
+async function showRemoteModal(sessionId) {
+  const { body, close } = _createModal('Remote-Verbindungen');
+
+  body.innerHTML = '<div class="sp-loading">Laden...</div>';
+
+  async function renderConnections() {
+    try {
+      const connections = await apiGetRemoteConnections();
+      body.innerHTML = '';
+
+      if (!connections || connections.length === 0) {
+        var empty = document.createElement('div');
+        empty.className = 'sp-loading';
+        empty.innerHTML = 'Keine Remote-Verbindungen aktiv.<br><br>' +
+          '<span style="font-size:var(--font-size);opacity:var(--semi-transparent)">Auf dem Windows-PC ausführen:<br>' +
+          '<code>irm ' + esc(location.origin) + '/remote.ps1 | iex</code></span>';
+        body.appendChild(empty);
+        return;
+      }
+
+      var hint = document.createElement('div');
+      hint.style.cssText = 'font-size:var(--font-size);opacity:var(--semi-transparent);margin-bottom:var(--box-spacing)';
+      hint.textContent = 'Verbindung auswählen um Remote-Befehle in dieser Session zu ermöglichen:';
+      body.appendChild(hint);
+
+      for (var i = 0; i < connections.length; i++) {
+        var conn = connections[i];
+        var card = document.createElement('div');
+        card.className = 'sp-block';
+        card.style.cursor = 'pointer';
+
+        var isAssigned = conn.assignedSessionId === sessionId;
+        var isAssignedOther = conn.assignedSessionId && conn.assignedSessionId !== sessionId;
+
+        var label = document.createElement('div');
+        label.className = 'sp-block-label';
+        var statusIcon = isAssigned ? 'fa-check-circle' : (isAssignedOther ? 'fa-link' : 'fa-desktop');
+        var statusColor = isAssigned ? 'color:var(--primary)' : '';
+        label.innerHTML = '<i class="fa ' + statusIcon + '" style="' + statusColor + '"></i> ' +
+          esc(conn.username || '?') + '@' + esc(conn.hostname || '?');
+        card.appendChild(label);
+
+        var content = document.createElement('div');
+        content.className = 'sp-block-content';
+        content.style.cssText = 'font-size:var(--font-size);display:flex;align-items:center;gap:var(--box-spacing)';
+
+        var info = document.createElement('span');
+        info.style.cssText = 'flex:1;opacity:var(--semi-transparent)';
+        var connDate = new Date(conn.connectedAt);
+        info.textContent = conn.os + ' • Verbunden seit ' + connDate.toLocaleTimeString('de');
+        content.appendChild(info);
+
+        var btn = document.createElement('button');
+        if (isAssigned) {
+          btn.textContent = 'Trennen';
+          btn.style.cssText = 'color:var(--dangerous)';
+        } else if (isAssignedOther) {
+          btn.textContent = 'Andere Session';
+          btn.disabled = true;
+          btn.style.cssText = 'opacity:var(--semi-transparent)';
+        } else {
+          btn.textContent = 'Verbinden';
+          btn.style.cssText = 'color:var(--primary)';
+        }
+        content.appendChild(btn);
+
+        card.appendChild(content);
+        body.appendChild(card);
+
+        // Event-Handler
+        (function(c, assigned) {
+          btn.addEventListener('click', async function(e) {
+            e.stopPropagation();
+            btn.disabled = true;
+            try {
+              if (assigned) {
+                await apiUnassignRemote(c.id);
+              } else {
+                await apiAssignRemote(c.id, sessionId);
+              }
+              await renderConnections();
+            } catch(err) {
+              showToast('Fehler: ' + err.message, 'error');
+              btn.disabled = false;
+            }
+          });
+        })(conn, isAssigned);
+      }
+    } catch (e) {
+      body.innerHTML = '<div class="sp-loading" style="color:var(--dangerous)">Fehler beim Laden: ' + esc(e.message) + '</div>';
+    }
+  }
+
+  await renderConnections();
+}
+
 // Event-Delegation für Krea-Thumbnails im Chat
 document.addEventListener('click', function(e) {
   var ref = e.target.closest('.krea-ref');