fix: Terminal Auth per JWT-Token statt leerem API-Key

- TerminalModal nutzt jetzt JWT aus localStorage (api.getToken()) fuer WS-Auth
- Backend Middleware: ?token= Query-Parameter fuer WebSocket JWT-Auth
- Behebt: api_key= leer -> 401 -> Terminal nicht erreichbar

backend/api/middleware.go

@@ -73,7 +73,7 @@ func (c *APIKeyCache) IsValid(key string) bool {
 // CombinedAuthWithCache - API-Key (aus DB-Cache) ODER JWT Token
 func CombinedAuthWithCache(cache *APIKeyCache, auth *AuthHandler, next http.Handler) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		// Try API key first
+		// Try API key first (Header oder Query-Parameter)
 		key := r.Header.Get("X-API-Key")
 		if key == "" {
 			key = r.URL.Query().Get("api_key")
@@ -83,11 +83,16 @@ func CombinedAuthWithCache(cache *APIKeyCache, auth *AuthHandler, next http.Hand
 			return
 		}
 
-		// Try JWT
+		// Try JWT — Authorization Header oder ?token= Query-Parameter (fuer WebSocket)
+		var jwtToken string
 		authHeader := r.Header.Get("Authorization")
 		if strings.HasPrefix(authHeader, "Bearer ") {
-			token := strings.TrimPrefix(authHeader, "Bearer ")
-			claims, err := auth.ValidateToken(token)
+			jwtToken = strings.TrimPrefix(authHeader, "Bearer ")
+		} else if t := r.URL.Query().Get("token"); t != "" {
+			jwtToken = t
+		}
+		if jwtToken != "" {
+			claims, err := auth.ValidateToken(jwtToken)
 			if err == nil {
 				ctx := context.WithValue(r.Context(), UserContextKey, claims)
 				next.ServeHTTP(w, r.WithContext(ctx))