upgrade structures and migrate to nextra v4

package.json

@@ -1,22 +1,24 @@
 {
-    "scripts": {
-        "dev": "next",
-        "build": "next build",
-        "start": "next start"
-    },
-    "dependencies": {
-        "@cloudflare/next-on-pages": "^1.13.7",
-        "@napi-rs/simple-git": "^0.1.19",
-        "@vercel/analytics": "^1.4.1",
-        "@vercel/speed-insights": "^1.1.0",
-        "next": "^15.3.5",
-        "nextra": "^3.3.1",
-        "nextra-theme-docs": "^3.3.1",
-        "react": "^18.3.1",
-        "react-dom": "^18.3.1",
-        "vercel": "^32.3.0"
-    },
-    "devDependencies": {
-        "@types/node": "22.10.7"
-    }
+  "scripts": {
+    "dev": "next dev",
+    "build": "cross-env NODE_OPTIONS='--max-old-space-size=16384' next build",
+    "build:test": "cross-env ANALYZE=true NODE_OPTIONS='--inspect --max-old-space-size=4096' next build",
+    "build:analyze": "cross-env ANALYZE=true NODE_OPTIONS='--max-old-space-size=16384' next build",
+    "start": "next start"
+  },
+  "dependencies": {
+    "@next/bundle-analyzer": "^15.3.5",
+    "@vercel/analytics": "^1.5.0",
+    "@vercel/speed-insights": "^1.2.0",
+    "cross-env": "^7.0.3",
+    "next": "^15.3.5",
+    "nextra": "^4.2.17",
+    "nextra-theme-docs": "^4.2.17",
+    "react": "^19.1.0",
+    "react-dom": "^19.1.0"
+  },
+  "devDependencies": {
+    "@types/node": "24.0.10",
+    "@types/react": "19.1.8"
+  }
 }