Add info about docker detach mode

Author: ntrogh

docs/copilot/chat/mcp-servers.md

@@ -140,7 +140,7 @@ Use the following JSON configuration format to define MCP servers.
     | Field | Description | Examples |
     |-------|-------------|----------|
     | `type` | Server connection type.  | `"stdio"` |
-    | `command` | Command to start the server executable. | `"npx"`,`"node"`, `"python"`, `"docker"` |
+    | `command` | Command to start the server executable. The command needs to be available on your system path or contain its full path.<br/>If you use docker, don't use the detach option. | `"npx"`,`"node"`, `"python"`, `"docker"` |
     | `args` | Array of arguments passed to the command. | `["server.py", "--port", "3000"]` |
     | `env` | Environment variables for the server. | `{"API_KEY": "${input:api-key}"}` |
     | `envFile` | Path to an `.env` from which to load additional environment variables. | `"${workspaceFolder}/.env"` |
@@ -303,6 +303,10 @@ Yes, you have several options to control which tools are active:
 - Add specific tools to your prompt by using the **Add Context** button or by typing `#`.
 - For more advanced control, you can use `.github/copilot-instructions.md` to fine-tune tool usage.
 
+### My docker-based MCP server is not starting
+
+Verify that the command arguments are correct and that the container is not running in detached mode (`-d` option). You can also check the MCP server output for any error messages (see [Troubleshooting](#troubleshooting)).
+
 ## Related resources
 
 - [Model Context Protocol Documentation](https://modelcontextprotocol.io/)