* mcp: add a devmode for MCP servers

Some ✈️ hacking. This adds a `dev` option to MCP servers with optional
properties that looks like:

```json
{
    "servers": {
        "everything": {
            "type": "stdio",
            "command": "node",
            "args": [
                "tsx",
                "${workspaceFolder}/index.ts"
            ],
            "dev": {
                "watch": "*.ts",
                "debug": "node"
            }
        }
    }
}
```

This does the following:

- Automatically starts the MCP server with VS Code
- With `watch` file patterns, restarts the server when those files are changed.
- With `debug: 'node' | 'python'`, will debug the server in that mode
- Make the Output view for the MCP server open more aggressively and
  promotes traffic log level to `info` (visible by default)

* separate debug action, support python debugging a bit