Launch server as localhost instead of 127.0.0.1 (#181)

Unless there's any strong reason to prefer the IP address over `localhost` that I'm not privy to, I'd like to propose changing wrangler to announce the server starting as localhost instead

Browsers can't set cookies to IP addresses, so any login or session tracking that a project might want to do won't work until the user switches to localhost, which can be the cause for some confusion if the dev isn't already familiar with that behaviour.

Co-authored-by: Greg Brimble <[email protected]>

packages/wrangler/src/pages.tsx

@@ -897,7 +897,7 @@ export const pages: BuilderCallback<unknown, unknown> = (yargs) => {
               if (proxyPort) {
                 try {
                   const url = new URL(request.url);
-                  url.host = `127.0.0.1:${proxyPort}`;
+                  url.host = `localhost:${proxyPort}`;
                   return await fetch(url, request);
                 } catch (thrown) {
                   console.error(`Could not proxy request: ${thrown}`);
@@ -935,10 +935,10 @@ export const pages: BuilderCallback<unknown, unknown> = (yargs) => {
         try {
           // `startServer` might throw if user code contains errors
           const server = await miniflare.startServer();
-          console.log(`Serving at http://127.0.0.1:${port}/`);
+          console.log(`Serving at http://localhost:${port}/`);
 
           if (process.env.BROWSER !== "none") {
-            const childProcess = await open(`http://127.0.0.1:${port}/`);
+            const childProcess = await open(`http://localhost:${port}/`);
             // fail silently if the open command doesn't work (e.g. in GitHub Codespaces)
             childProcess.on("error", (_err) => {});
           }