Run brew lgtm on stop in AI hooks

- replace the per-edit `style --changed --fix` and `typecheck`
  `PostToolUse` hooks and the `tests --changed` `Stop` hook with a
  single `./bin/brew lgtm` on `Stop` in `.claude/settings.json`
- add a matching Codex `Stop` hook in `.codex/hooks.json`, unignoring
  `.codex` like `.claude`, so both agents run the same check
- `brew lgtm` runs typecheck, style and the relevant tests together

.claude/settings.json

@@ -1,26 +1,11 @@
 {
   "hooks": {
-    "PostToolUse": [
-      {
-        "matcher": "Edit|Write",
-        "hooks": [
-          {
-            "type": "command",
-            "command": "./bin/brew style --changed --fix"
-          },
-          {
-            "type": "command",
-            "command": "./bin/brew typecheck"
-          }
-        ]
-      }
-    ],
     "Stop": [
       {
         "hooks": [
           {
             "type": "command",
-            "command": "./bin/brew tests --changed",
+            "command": "./bin/brew lgtm",
             "timeout": 360
           }
         ]

.codex/hooks.json

@@ -0,0 +1,15 @@
+{
+  "hooks": {
+    "Stop": [
+      {
+        "hooks": [
+          {
+            "type": "command",
+            "command": "./bin/brew lgtm",
+            "timeout": 360
+          }
+        ]
+      }
+    ]
+  }
+}

.gitignore

@@ -219,6 +219,7 @@
 # Unignore AI configuration
 !/.cursor
 !/.claude
+!/.codex
 
 # Ignore local AI configuration
 /.claude/settings.local.json