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/readable-stream/writable.js

@@ -0,0 +1,8 @@
+var Stream = require("stream")
+var Writable = require("./lib/_stream_writable.js")
+
+if (process.env.READABLE_STREAM === 'disable') {
+  module.exports = Stream && Stream.Writable || Writable
+} else {
+  module.exports = Writable
+}