fix(api-gateway): home server home page (#949)

* feat: add home server home page message

* fix: upgrade yarn

packages/api-gateway/src/Controller/FallbackController.ts

@@ -1,9 +1,18 @@
+import { Request, Response } from 'express'
 import { BaseHttpController, all, controller, results } from 'inversify-express-utils'
 
 @controller('')
 export class FallbackController extends BaseHttpController {
   @all('*')
-  public async fallback(): Promise<results.NotFoundResult> {
+  public async fallback(request: Request, response: Response): Promise<void | results.NotFoundResult> {
+    if (request.path === '/' && request.method === 'GET') {
+      response.send(
+        '<!DOCTYPE html><html lang="en"><head><meta name="robots" content="noindex"></head><body>Your home server is up and running! Enter the URL of this page into Standard Notes when registering or signing in to begin using your home server.</body></html>',
+      )
+
+      return
+    }
+
     return this.notFound()
   }
 }