docs: fix stale milla-jovovich org URLs in website and plugin manifests (#787)

Follow-up to #766 which covers version.py, pyproject.toml, README,
CHANGELOG, and CONTRIBUTING. These 11 files still had the old org
name in URLs:

- website/ (VitePress config + 6 docs pages)
- .claude-plugin/ (plugin.json repository, README marketplace command)
- .codex-plugin/ (plugin.json URLs, README links)

Author name fields are intentionally unchanged.

.codex-plugin/README.md

@@ -35,7 +35,7 @@ codex /init
 1. Clone the MemPalace repository:
 
 ```bash
-git clone https://github.com/milla-jovovich/mempalace.git
+git clone https://github.com/MemPalace/mempalace.git
 cd mempalace
 ```
 
@@ -71,5 +71,5 @@ Set the `MEMPAL_DIR` environment variable to a directory path to automatically r
 
 ## Support
 
-- Repository: https://github.com/milla-jovovich/mempalace
-- Issues: https://github.com/milla-jovovich/mempalace/issues
+- Repository: https://github.com/MemPalace/mempalace
+- Issues: https://github.com/MemPalace/mempalace/issues

.codex-plugin/plugin.json

@@ -5,8 +5,8 @@
   "author": {
     "name": "milla-jovovich"
   },
-  "homepage": "https://github.com/milla-jovovich/mempalace",
-  "repository": "https://github.com/milla-jovovich/mempalace",
+  "homepage": "https://github.com/MemPalace/mempalace",
+  "repository": "https://github.com/MemPalace/mempalace",
   "license": "MIT",
   "keywords": [
     "memory",
@@ -39,9 +39,9 @@
       "Read",
       "Write"
     ],
-    "websiteURL": "https://github.com/milla-jovovich/mempalace",
-    "privacyPolicyURL": "https://github.com/milla-jovovich/mempalace",
-    "termsOfServiceURL": "https://github.com/milla-jovovich/mempalace",
+    "websiteURL": "https://github.com/MemPalace/mempalace",
+    "privacyPolicyURL": "https://github.com/MemPalace/mempalace",
+    "termsOfServiceURL": "https://github.com/MemPalace/mempalace",
     "defaultPrompt": [
       "Search my memories for recent decisions",
       "Mine this project into my memory palace",