Build: add Dockerfile for dev, devcontainer settings

Author: gitgitWi

package.json

@@ -13,9 +13,9 @@
   "dependencies": {
     "@mdx-js/loader": "^1.6.22",
     "@next/mdx": "^11.1.0",
-    "next": "11.1.1",
-    "react": "17.0.2",
-    "react-dom": "17.0.2",
+    "next": "12",
+    "react": "^17.0.2",
+    "react-dom": "^17.0.2",
     "sass": "^1.38.0"
   },
   "devDependencies": {