fix(cli): create .bat wrapper on Windows instead of POSIX shell script

On Windows, hermes profile create produced a #!/bin/sh script that the
shell cannot execute.  Now creates a .bat file with @echo off + %* on
Windows, and keeps the POSIX shell script on macOS/Linux.

Also fixes check_alias_collision to use 'where' instead of 'which' on
Windows, and remove_wrapper_script to find .bat files.

Fixes #34708

tests/hermes_cli/test_profiles.py

@@ -600,6 +600,88 @@ class TestAliasCollision:
         assert result is not None
         assert "reserved" in result.lower()
 
+    def test_uses_where_on_windows(self, profile_env, monkeypatch):
+        monkeypatch.setattr("sys.platform", "win32")
+        with patch("subprocess.run") as mock_run:
+            mock_run.return_value = MagicMock(returncode=1, stdout="")
+            check_alias_collision("mybot")
+        call_args = mock_run.call_args[0][0]
+        assert call_args[0] == "where"
+
+    def test_uses_which_on_posix(self, profile_env, monkeypatch):
+        monkeypatch.setattr("sys.platform", "darwin")
+        with patch("subprocess.run") as mock_run:
+            mock_run.return_value = MagicMock(returncode=1, stdout="")
+            check_alias_collision("mybot")
+        call_args = mock_run.call_args[0][0]
+        assert call_args[0] == "which"
+
+    def test_windows_checks_bat_extension(self, profile_env, monkeypatch):
+        monkeypatch.setattr("sys.platform", "win32")
+        wrapper_dir = profile_env / ".local" / "bin"
+        wrapper_dir.mkdir(parents=True, exist_ok=True)
+        bat_path = wrapper_dir / "mybot.bat"
+        bat_path.write_text("@echo off\r\nhermes -p mybot %*\r\n")
+        with patch("subprocess.run") as mock_run:
+            mock_run.return_value = MagicMock(
+                returncode=0, stdout=str(bat_path),
+            )
+            result = check_alias_collision("mybot")
+        assert result is None  # our own wrapper, safe to overwrite
+
+
+# ===================================================================
+# TestWrapperScript
+# ===================================================================
+
+class TestWrapperScript:
+    """Tests for create_wrapper_script() and remove_wrapper_script()."""
+
+    def test_creates_sh_on_posix(self, profile_env, monkeypatch):
+        monkeypatch.setattr("sys.platform", "darwin")
+        from hermes_cli.profiles import create_wrapper_script
+        wrapper = create_wrapper_script("mybot")
+        assert wrapper is not None
+        assert wrapper.name == "mybot"
+        content = wrapper.read_text()
+        assert content.startswith("#!/bin/sh")
+        assert "hermes -p mybot" in content
+
+    def test_creates_bat_on_windows(self, profile_env, monkeypatch):
+        monkeypatch.setattr("sys.platform", "win32")
+        from hermes_cli.profiles import create_wrapper_script
+        wrapper = create_wrapper_script("mybot")
+        assert wrapper is not None
+        assert wrapper.name == "mybot.bat"
+        content = wrapper.read_text()
+        assert "@echo off" in content
+        assert "hermes -p mybot" in content
+        assert "%*" in content
+
+    def test_remove_finds_bat_on_windows(self, profile_env, monkeypatch):
+        monkeypatch.setattr("sys.platform", "win32")
+        from hermes_cli.profiles import create_wrapper_script, remove_wrapper_script
+        wrapper = create_wrapper_script("mybot")
+        assert wrapper is not None
+        assert wrapper.exists()
+        removed = remove_wrapper_script("mybot")
+        assert removed is True
+        assert not wrapper.exists()
+
+    def test_remove_finds_sh_on_posix(self, profile_env, monkeypatch):
+        monkeypatch.setattr("sys.platform", "darwin")
+        from hermes_cli.profiles import create_wrapper_script, remove_wrapper_script
+        wrapper = create_wrapper_script("mybot")
+        assert wrapper is not None
+        assert wrapper.exists()
+        removed = remove_wrapper_script("mybot")
+        assert removed is True
+        assert not wrapper.exists()
+
+    def test_remove_returns_false_when_absent(self, profile_env):
+        from hermes_cli.profiles import remove_wrapper_script
+        assert remove_wrapper_script("nonexistent") is False
+
 
 # ===================================================================
 # TestRenameProfile