feat: self update npm deps on hermes update

tests/hermes_cli/test_cmd_update.py

@@ -106,6 +106,49 @@ class TestCmdUpdateBranchFallback:
         pull_cmds = [c for c in commands if "pull" in c]
         assert len(pull_cmds) == 0
 
+    @patch("shutil.which")
+    @patch("subprocess.run")
+    def test_update_refreshes_repo_and_tui_node_dependencies(
+        self, mock_run, mock_which, mock_args
+    ):
+        mock_which.side_effect = {"uv": "/usr/bin/uv", "npm": "/usr/bin/npm"}.get
+        mock_run.side_effect = _make_run_side_effect(
+            branch="main", verify_ok=True, commit_count="1"
+        )
+
+        cmd_update(mock_args)
+
+        npm_calls = [
+            (call.args[0], call.kwargs.get("cwd"))
+            for call in mock_run.call_args_list
+            if call.args and call.args[0][0] == "/usr/bin/npm"
+        ]
+
+        assert npm_calls == [
+            (
+                [
+                    "/usr/bin/npm",
+                    "install",
+                    "--silent",
+                    "--no-fund",
+                    "--no-audit",
+                    "--progress=false",
+                ],
+                PROJECT_ROOT,
+            ),
+            (
+                [
+                    "/usr/bin/npm",
+                    "install",
+                    "--silent",
+                    "--no-fund",
+                    "--no-audit",
+                    "--progress=false",
+                ],
+                PROJECT_ROOT / "ui-tui",
+            ),
+        ]
+
     def test_update_non_interactive_skips_migration_prompt(self, mock_args, capsys):
         """When stdin/stdout aren't TTYs, config migration prompt is skipped."""
         with patch("shutil.which", return_value=None), patch(