fix(dashboard): remove Authorization header and withCredentials from SSE connections

SSE connections to /api/live-log are same-origin (VITE_API_BASE is empty
in production, resolves to relative /api path). The Authorization header
and withCredentials:true triggered CORS preflight (OPTIONS) requests,
but the SSE route only handles GET, causing the preflight to fail.

dashboard/src/components/shared/ConsoleDisplayer.vue

@@ -123,16 +123,10 @@ export default {
 
       console.log(`正在连接日志流... (尝试次数: ${this.retryAttempts})`);
 
-      const token = localStorage.getItem("token");
-
       this.eventSource = new EventSourcePolyfill(
         resolveApiUrl("/api/live-log"),
         {
-          headers: {
-            Authorization: token ? `Bearer ${token}` : "",
-          },
           heartbeatTimeout: 300000,
-          withCredentials: true,
         },
       );
 

dashboard/src/components/shared/TraceDisplayer.vue

@@ -180,16 +180,10 @@ export default {
         this.eventSource = null;
       }
 
-      const token = localStorage.getItem("token");
-
       this.eventSource = new EventSourcePolyfill(
         resolveApiUrl("/api/live-log"),
         {
-          headers: {
-            Authorization: token ? `Bearer ${token}` : "",
-          },
           heartbeatTimeout: 300000,
-          withCredentials: true,
         },
       );