fix: Update nginx config to use dynamic DNS resolution

- Replace upstream blocks with resolver directive
- Use variables for backend addresses to avoid startup errors
- Simplify configuration with single server block
- Add health check endpoint

server/api/node_modules/slash/readme.md

@@ -0,0 +1,44 @@
+# slash [![Build Status](https://travis-ci.org/sindresorhus/slash.svg?branch=master)](https://travis-ci.org/sindresorhus/slash)
+
+> Convert Windows backslash paths to slash paths: `foo\\bar` ➔ `foo/bar`
+
+[Forward-slash paths can be used in Windows](http://superuser.com/a/176395/6877) as long as they're not extended-length paths and don't contain any non-ascii characters.
+
+This was created since the `path` methods in Node.js outputs `\\` paths on Windows.
+
+
+## Install
+
+```
+$ npm install slash
+```
+
+
+## Usage
+
+```js
+const path = require('path');
+const slash = require('slash');
+
+const string = path.join('foo', 'bar');
+// Unix    => foo/bar
+// Windows => foo\\bar
+
+slash(string);
+// Unix    => foo/bar
+// Windows => foo/bar
+```
+
+
+## API
+
+### slash(path)
+
+Type: `string`
+
+Accepts a Windows backslash path and returns a path with forward slashes.
+
+
+## License
+
+MIT © [Sindre Sorhus](https://sindresorhus.com)