chore: rename package from @hykocx/zen to @zen/core

Update all references across source files, documentation, and
configuration to reflect the new package scope and name. This includes
updating `.npmrc` registry config, install instructions, module
examples, and all import path comments throughout the codebase.

package.json

@@ -1,13 +1,13 @@
 {
-  "name": "@hykocx/zen",
-  "version": "1.3.2",
+  "name": "@zen/core",
+  "version": "1.3.3",
   "description": "Un CMS construit sur l'essentiel, rien de plus, rien de moins.",
   "repository": {
     "type": "git",
-    "url": "https://git.hyko.cx/hykocx/zen.git"
+    "url": "https://git.hyko.cx/zen/core.git"
   },
   "publishConfig": {
-    "registry": "https://git.hyko.cx/api/packages/hykocx/npm/"
+    "registry": "https://git.hyko.cx/api/packages/zen/npm/"
   },
   "license": "GPL-3.0-only",
   "author": "Hyko",