e2e | rework setup `host` and `port` option

Describe the feature

I think we should consider reworking the host and port options for the e2e setup() function.

In my opinion, it is currently not possible to specify a base URL with the default setup dev/test server. Sometimes e2e needs a non-localhost base URL to be able to implement csrf token/session cookies.

The current workaround would be to start the dev server before testing.

Proposal

await setup({
  runner: 'vitest',
  // testServer: false // run against an already running server
  testServer: {
    build: true, // boolean
    host: '0.0.0.0', // or whatever
    port: 80,
  },
  baseURL: 'http://frontend.local.test', // https://playwright.dev/docs/api/class-testoptions#test-options-base-url 
  browser: true,
})

baseURL can be different form testServer.host. (echo "127.0.0.1 frontend.local.test" >> /etc/hosts)

Additional information

• Would you be willing to help implement this feature?
• Could this feature be implemented as a module?

Final checks

• Read the contribution guide.
• Check existing discussions and issues.

Start at the e2e setup() entry point and read the current dev/test server option handling. Compare the proposed testServer host, port, build, already-running-server, and baseURL behavior with the Vitest runner and browser flow; done means these options support the stated non-localhost base URL and server configurations.