docs: fix inconsistent commandRegex example in policy engine (#19027)

packages/core/src/policy/toml-loader.test.ts

@@ -111,6 +111,24 @@ priority = 100
       expect(result.errors).toHaveLength(0);
     });
 
+    it('should NOT match if ^ is used in commandRegex because it matches against full JSON', async () => {
+      const result = await runLoadPoliciesFromToml(`
+[[rule]]
+toolName = "run_shell_command"
+commandRegex = "^git status"
+decision = "allow"
+priority = 100
+`);
+
+      expect(result.rules).toHaveLength(1);
+      // The generated pattern is "command":"^git status
+      // This will NOT match '{"command":"git status"}' because of the '{"' at the start.
+      expect(
+        result.rules[0].argsPattern?.test('{"command":"git status"}'),
+      ).toBe(false);
+      expect(result.errors).toHaveLength(0);
+    });
+
     it('should expand toolName array', async () => {
       const result = await runLoadPoliciesFromToml(`
 [[rule]]