Lint rules and flow annotations for rest of the files

server/api/middlewares/apiWrapper.js

@@ -1,9 +1,16 @@
-export default function apiWrapper(_options) {
-  return async function apiWrapperMiddleware(ctx, next) {
+// @flow
+import { type Context } from 'koa';
+
+export default function apiWrapper() {
+  return async function apiWrapperMiddleware(
+    ctx: Context,
+    next: () => Promise<void>
+  ) {
     await next();
 
     const ok = ctx.status < 400;
 
+    // $FlowFixMe
     ctx.body = {
       ...ctx.body,
       status: ctx.status,