fix: resolve EADDRINUSE port conflict — Node.js now listens on internal port 4000

Nginx listens publicly on 2087/2083 and reverse-proxies to 127.0.0.1:4000.
Previously both Nginx and Node.js were trying to bind port 2087 causing the
nixpanel service to crash-loop. HOST changed to 127.0.0.1 so the API is
not directly reachable from outside.

Bumps version to 0.3.1.

server/src/app.ts

@@ -73,7 +73,7 @@ export async function buildApp() {
 
   fastify.get('/api/health', async () => ({
     status: 'ok',
-    version: '0.3.0',
+    version: '0.3.1',
     timestamp: new Date().toISOString(),
   }))
 

server/src/config.ts

@@ -16,8 +16,8 @@ export const config = {
 
   server: {
     host: optional('HOST', '0.0.0.0'),
-    nixserverPort: parseInt(optional('NIXSERVER_PORT', '2087'), 10),
-    nixclientPort: parseInt(optional('NIXCLIENT_PORT', '2083'), 10),
+    nixserverPort: parseInt(optional('NIXSERVER_PORT', '4000'), 10),
+    nixclientPort: parseInt(optional('NIXCLIENT_PORT', '4001'), 10),
   },
 
   db: {

server/src/index.ts

@@ -13,10 +13,11 @@ async function start() {
 
     app = await buildApp()
 
-    // NixServer on port 2087
+    // Node.js listens on internal port (Nginx proxies public 2087/2083 → here)
     await app.listen({ port: config.server.nixserverPort, host: config.server.host })
-    console.log(`NixServer running on port ${config.server.nixserverPort}`)
-    console.log(`NixClient API running on port ${config.server.nixserverPort} (/api/cpanel)`)
+    console.log(`NixPanel API running on ${config.server.host}:${config.server.nixserverPort}`)
+    console.log(`NixServer admin → http://127.0.0.1:${config.server.nixserverPort}/api/`)
+    console.log(`NixClient user  → http://127.0.0.1:${config.server.nixserverPort}/api/cpanel/`)
 
   } catch (err) {
     console.error('Failed to start server:', err)