deps: change min required nodejs to v20 (breaking)

docs/index.md

@@ -6,7 +6,7 @@ Quartz is a fast, batteries-included static-site generator that transforms Markd
 
 ## 🪴 Get Started
 
-Quartz requires **at least [Node](https://nodejs.org/) v18.14** and `npm` v9.3.1 to function correctly. Ensure you have this installed on your machine before continuing.
+Quartz requires **at least [Node](https://nodejs.org/) v20** and `npm` v9.3.1 to function correctly. Ensure you have this installed on your machine before continuing.
 
 Then, in your terminal of choice, enter the following commands line by line:
 

package-lock.json

@@ -85,7 +85,7 @@
         "typescript": "^5.5.3"
       },
       "engines": {
-        "node": ">=18.14",
+        "node": "20 || >=22",
         "npm": ">=9.3.1"
       }
     },

package.json

@@ -21,7 +21,7 @@
   },
   "engines": {
     "npm": ">=9.3.1",
-    "node": ">=18.14"
+    "node": "20 || >=22"
   },
   "keywords": [
     "site generator",