Add unit tests for LoginButton component with comprehensive coverage

.vscode/launch.json

@@ -30,6 +30,13 @@
       ],
       "cwd": "${workspaceFolder}/frontend/vue-app",
       "console": "integratedTerminal"
+    },
+    {
+      "name": "Chrome: Attach to Vue App",
+      "type": "chrome",
+      "request": "launch",
+      "url": "https://localhost:5173", // or your Vite dev server port
+      "webRoot": "${workspaceFolder}/frontend/vue-app"
     }
   ],
   "compounds": [
@@ -37,7 +44,8 @@
       "name": "Full Stack (Backend + Frontend)",
       "configurations": [
         "Python: Flask",
-        "Vue: Dev Server"
+        "Vue: Dev Server",
+        "Chrome: Attach to Vue App"
       ]
     }
   ]