Devcontainers: use simpler image, disable IPv6

Previous image did not work on Mac ARM machines, so used a simpler one.

Also, port forwarding did not work ootb as VSCode's forwarding feature
does not support IPv6 (see vitejs/vite#16522).
Fix is to disable IPv6 in the container.

Author: chgeo

.devcontainer/devcontainer.json

@@ -1,11 +1,15 @@
 {
-    "image":"mcr.microsoft.com/devcontainers/universal:2",
+    "image":"mcr.microsoft.com/vscode/devcontainers/javascript-node:22",
     "customizations": {
         "vscode": {
             "extensions": [
                 "fcrespo82.markdown-table-formatter",
                 "vue.volar"
             ]
         }
-    }
+    },
+    "runArgs": [
+        // disable IPv6, see https://github.com/vitejs/vite/issues/16522
+        "--sysctl", "net.ipv6.conf.all.disable_ipv6=1"
+    ]
 }