fix(server): play_audio leaks file handle — open() without context manager

[alfonsodg]

Problem

play_audio() opens a file without a context manager, causing a file handle leak:

play(open(file_path, "rb").read())

The file descriptor is never explicitly closed.

Exact location

• File: minimax_mcp/server.py
• Function: play_audio(), the else branch

Impact

• File descriptor leak on every call
• On systems with low fd limits, repeated calls can exhaust file descriptors
• ResourceWarning in Python 3.12+

Proposed solution

def play_audio(input_file_path: str, is_url: bool = False) -> TextContent:
    if is_url:
        response = requests.get(input_file_path, timeout=30)
        response.raise_for_status()
        play(response.content)
    else:
        file_path = process_input_file(input_file_path)
        with open(file_path, "rb") as f:
            play(f.read())
    return TextContent(type="text", text=f"Successfully played audio file: {input_file_path}")

Also adds timeout to the URL download and raise_for_status() for error handling.

Acceptance criteria

• File opened with context manager (with statement)
• No ResourceWarning when running with -Wd flag
• URL download has timeout and error handling