Handle invalid commands gracefully, such as `mcpc login`

[jirispilka]

Even though mcpc login is invalid command, the erorr should be handled gracefully.

jirka@apify  ~  mcpc login 

[McpClient:mcpc] Failed to connect: TypeError: fetch failed
    at node:internal/deps/undici/undici:13502:13
    at process.processTicksAndRejections (node:internal/process/task_queues:105:5)
    at async StreamableHTTPClientTransport.send (file:///home/jirka/.nvm/versions/node/v22.14.0/lib/node_modules/@apify/mcpc/node_modules/@modelcontextprotocol/sdk/dist/esm/client/streamableHttp.js:306:30) {
  [cause]: Error: getaddrinfo ENOTFOUND login
      at GetAddrInfoReqWrap.onlookupall [as oncomplete] (node:dns:120:26) {
    errno: -3008,
    code: 'ENOTFOUND',
    syscall: 'getaddrinfo',
    hostname: 'login'
  }
}
Fatal error: NetworkError: Failed to connect to MCP server: Failed to connect to MCP server: fetch failed
    at withMcpClient (file:///home/jirka/.nvm/versions/node/v22.14.0/lib/node_modules/@apify/mcpc/dist/cli/helpers.js:182:15)
    at process.processTicksAndRejections (node:internal/process/task_queues:105:5)
    at async Module.showServerDetails (file:///home/jirka/.nvm/versions/node/v22.14.0/lib/node_modules/@apify/mcpc/dist/cli/commands/sessions.js:306:5)
    at async handleCommands (file:///home/jirka/.nvm/versions/node/v22.14.0/lib/node_modules/@apify/mcpc/dist/cli/index.js:206:9)
    at async main (file:///home/jirka/.nvm/versions/node/v22.14.0/lib/node_modules/@apify/mcpc/dist/cli/index.js:130:9) {
  code: 3,
  details: {
    originalError: NetworkError: Failed to connect to MCP server: fetch failed
        at McpClient.connect (file:///home/jirka/.nvm/versions/node/v22.14.0/lib/node_modules/@apify/mcpc/dist/core/mcp-client.js:59:19)
        at process.processTicksAndRejections (node:internal/process/task_queues:105:5)
        at async createMcpClient (file:///home/jirka/.nvm/versions/node/v22.14.0/lib/node_modules/@apify/mcpc/dist/core/factory.js:22:9)
        at async withMcpClient (file:///home/jirka/.nvm/versions/node/v22.14.0/lib/node_modules/@apify/mcpc/dist/cli/helpers.js:175:18)
        at async Module.showServerDetails (file:///home/jirka/.nvm/versions/node/v22.14.0/lib/node_modules/@apify/mcpc/dist/cli/commands/sessions.js:306:5)
        at async handleCommands (file:///home/jirka/.nvm/versions/node/v22.14.0/lib/node_modules/@apify/mcpc/dist/cli/index.js:206:9)
        at async main (file:///home/jirka/.nvm/versions/node/v22.14.0/lib/node_modules/@apify/mcpc/dist/cli/index.js:130:9) {
      code: 3,
      details: [Object]
    }
  }
}