feat(pytest): Add TempServer for temporary tmux server management

Add TempServer function to pytest_plugin.py that creates a temporary tmux server
that cleans up after itself. This is similar to the server pytest fixture but can
be used outside of pytest contexts.

- Move and rename TempTmuxServer to TempServer in pytest_plugin.py
- Add comprehensive tests for TempServer functionality:
  - Basic server creation and cleanup
  - Custom socket name support
  - Config file loading
  - Multiple server isolation
  - Proper cleanup verification
- Use fin() for cleanup instead of __del__
- Remove old implementation from test.py

This provides a more flexible way to create temporary tmux servers for testing
and development purposes, while ensuring proper cleanup.

Author: tony

src/libtmux/pytest_plugin.py

@@ -256,3 +256,44 @@ def session(
     assert TEST_SESSION_NAME != "tmuxp"
 
     return session
+
+
+def TempServer(socket_name: str | None = None, **kwargs: t.Any) -> Server:
+    """Create a temporary tmux server that cleans up after itself.
+
+    This is similar to the server pytest fixture, but can be used outside of pytest.
+    The server will be killed when the object is garbage collected.
+
+    Parameters
+    ----------
+    socket_name : str, optional
+        Name for the tmux socket. If not provided, a random one will be generated.
+    **kwargs : dict
+        Additional arguments to pass to Server constructor
+
+    Returns
+    -------
+    Server
+        A Server instance that will clean up after itself
+
+    Examples
+    --------
+    >>> server = TempServer()
+    >>> server.new_session()
+    Session($... ...)
+    >>> server.is_alive()
+    True
+    >>> del server  # Server is automatically killed
+    """
+    if socket_name is None:
+        socket_name = f"libtmux_test{next(namer)}"
+
+    server = Server(socket_name=socket_name, **kwargs)
+
+    def fin() -> None:
+        """Kill server if it exists."""
+        if server.is_alive():
+            server.kill()
+
+    server.__del__ = fin  # type: ignore
+    return server

tests/test_pytest_plugin.py

@@ -2,7 +2,9 @@
 
 from __future__ import annotations
 
+import pathlib
 import textwrap
+import time
 import typing as t
 
 if t.TYPE_CHECKING:
@@ -71,3 +73,93 @@ def test_repo_git_remote_checkout(
     # Test
     result = pytester.runpytest(str(first_test_filename))
     result.assert_outcomes(passed=1)
+
+
+def test_temp_server() -> None:
+    """Test TempServer creates and cleans up server."""
+    from libtmux.pytest_plugin import TempServer
+
+    server = TempServer()
+    assert server.is_alive() is False  # Server not started yet
+
+    session = server.new_session()
+    assert server.is_alive() is True
+    assert len(server.sessions) == 1
+    assert session.session_name is not None
+
+    # Test custom socket name
+    custom_server = TempServer(socket_name="test_custom")
+    assert custom_server.socket_name == "test_custom"
+
+    # Test cleanup
+    del server
+    del custom_server
+
+
+def test_temp_server_with_config(tmp_path: pathlib.Path) -> None:
+    """Test TempServer with custom config."""
+    from libtmux.pytest_plugin import TempServer
+
+    config_file = tmp_path / "tmux.conf"
+    config_file.write_text("set -g status off", encoding="utf-8")
+
+    server = TempServer(config_file=str(config_file))
+    session = server.new_session()
+
+    # Verify config was loaded by checking status
+    assert session.cmd("show-options", "-g", "status").stdout[0] == "status off"
+
+    del server
+
+
+def test_temp_server_cleanup() -> None:
+    """Test TempServer properly cleans up after itself."""
+    from libtmux.pytest_plugin import TempServer
+
+    server = TempServer()
+    socket_name = server.socket_name
+    assert socket_name is not None
+
+    # Create multiple sessions
+    server.new_session(session_name="test1")
+    server.new_session(session_name="test2")
+    assert len(server.sessions) == 2
+
+    # Verify server is alive
+    assert server.is_alive() is True
+
+    # Delete server and verify cleanup
+    server.kill()
+    del server
+    time.sleep(0.1)  # Give time for cleanup
+
+    # Create new server with same socket name to verify old one was cleaned up
+    new_server = TempServer(socket_name=socket_name)
+    assert new_server.is_alive() is False  # Server not started yet
+    new_server.new_session()  # This should work if old server was cleaned up
+    assert new_server.is_alive() is True
+    del new_server
+
+
+def test_temp_server_multiple() -> None:
+    """Test multiple TempServer instances can coexist."""
+    from libtmux.pytest_plugin import TempServer
+
+    server1 = TempServer()
+    server2 = TempServer()
+
+    # Each server should have a unique socket
+    assert server1.socket_name != server2.socket_name
+
+    # Create sessions in each server
+    server1.new_session(session_name="test1")
+    server2.new_session(session_name="test2")
+
+    # Verify sessions are in correct servers
+    assert any(s.session_name == "test1" for s in server1.sessions)
+    assert any(s.session_name == "test2" for s in server2.sessions)
+    assert not any(s.session_name == "test1" for s in server2.sessions)
+    assert not any(s.session_name == "test2" for s in server1.sessions)
+
+    del server1
+    del server2