stdio MCP 转发 DISPLAY

本机有显示器、MCP 却只有 snapshot 时转发图形会话变量。键是 env_vars，不是 env_args。修不了沙箱。

[mcp_servers.playwright]
command = "npx"
args = ["-y", "@playwright/mcp@latest"]
env_vars = ["DISPLAY", "WAYLAND_DISPLAY", "XAUTHORITY", "XDG_RUNTIME_DIR"]
startup_timeout_sec = 20
enabled = true