Fix Codex hook manifest schema

.codex/hooks.json

@@ -1,5 +1,4 @@
 {
-  "description": "Impeccable design detector: runs after Edit/Write/apply_patch on UI files and surfaces findings as system reminders.",
   "hooks": {
     "PostToolUse": [
       {
@@ -7,7 +6,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "node \"$(git rev-parse --show-toplevel)/.agents/skills/impeccable/scripts/hook.mjs\"",
+            "command": "node \".agents/skills/impeccable/scripts/hook.mjs\"",
             "timeout": 5,
             "statusMessage": "Checking UI changes"
           }