Enhance configuration and layout: add environment variables, improve metadata, and update content section keys for consistency

Co-authored-by: Copilot <copilot@github.com>

package-lock.json

@@ -14,7 +14,8 @@
         "tailwindcss": "^4.2.4"
       },
       "devDependencies": {
-        "@tailwindcss/typography": "^0.5.19"
+        "@tailwindcss/typography": "^0.5.19",
+        "@types/node": "^25.6.0"
       },
       "engines": {
         "node": ">=22.12.0"
@@ -1982,6 +1983,16 @@
         "@types/unist": "*"
       }
     },
+    "node_modules/@types/node": {
+      "version": "25.6.0",
+      "resolved": "https://registry.npmjs.org/@types/node/-/node-25.6.0.tgz",
+      "integrity": "sha512-+qIYRKdNYJwY3vRCZMdJbPLJAtGjQBudzZzdzwQYkEPQd+PJGixUL5QfvCLDaULoLv+RhT3LDkwEfKaAkgSmNQ==",
+      "devOptional": true,
+      "license": "MIT",
+      "dependencies": {
+        "undici-types": "~7.19.0"
+      }
+    },
     "node_modules/@types/unist": {
       "version": "3.0.3",
       "resolved": "https://registry.npmjs.org/@types/unist/-/unist-3.0.3.tgz",
@@ -5675,6 +5686,13 @@
       "integrity": "sha512-Ql87qFHB3s/De2ClA9e0gsnS6zXG27SkTiSJwjCc9MebbfapQfuPzumMIUMi38ezPZVNFcHI9sUIepeQfw8J8Q==",
       "license": "MIT"
     },
+    "node_modules/undici-types": {
+      "version": "7.19.2",
+      "resolved": "https://registry.npmjs.org/undici-types/-/undici-types-7.19.2.tgz",
+      "integrity": "sha512-qYVnV5OEm2AW8cJMCpdV20CDyaN3g0AjDlOGf1OW4iaDEx8MwdtChUp4zu4H0VP3nDRF/8RKWH+IPp9uW0YGZg==",
+      "devOptional": true,
+      "license": "MIT"
+    },
     "node_modules/unified": {
       "version": "11.0.5",
       "resolved": "https://registry.npmjs.org/unified/-/unified-11.0.5.tgz",