feat: add Claude tool hooks configuration

Add .claude/settings.json to configure pre and post tool use
hooks for Edit, MultiEdit, and Write operations. These hooks
integrate with the but CLI to execute validation and cleanup
commands before and after file modifications, and on stop
events.

.claude/settings.json

@@ -0,0 +1,37 @@
+{
+  "hooks": {
+    "PreToolUse": [
+      {
+        "matcher": "Edit|MultiEdit|Write",
+        "hooks": [
+          {
+            "type": "command",
+            "command": "but claude pre-tool"
+          }
+        ]
+      }
+    ],
+    "PostToolUse": [
+      {
+        "matcher": "Edit|MultiEdit|Write",
+        "hooks": [
+          {
+            "type": "command",
+            "command": "but claude post-tool"
+          }
+        ]
+      }
+    ],
+    "Stop": [
+      {
+        "matcher": "",
+        "hooks": [
+          {
+            "type": "command",
+            "command": "but claude stop"
+          }
+        ]
+      }
+    ]
+  }
+}