feat: migrate application port from 3000 to 4001 and fix circular dependencies

- Change default port to 4001 across all configuration files (server.js, docker-compose.yml, .env, Dockerfile)
- Update frontend API URL to use new port 4001
- Fix circular dependency issues in route files by using process.env.SERVER_DIR instead of importing from server.js
- Apply to all routes: auth.js, backup.js, logs.js, players.js, rcon.js, server.js, whitelist.js
- Fix environment variable loading in start.sh to properly handle paths with spaces
- Quote SERVER_DIR path in .env to preserve spaces in directory paths
- Update all documentation references from port 3000 to 4001 (README, QUICKSTART, CONFIGURATION, INDEX)
- Remove debug console.log statements from auth.js
- Remove test utility file test-ops.js

Fixes: Port conflict issues, circular dependency warnings, environment variable parsing

backend/src/routes/auth.js

@@ -2,10 +2,10 @@ const express = require('express');
 const bcrypt = require('bcryptjs');
 const fs = require('fs-extra');
 const path = require('path');
-const { SERVER_DIR } = require('../server');
 
 const router = express.Router();
 const USERS_FILE = path.join(__dirname, '../../data/users.json');
+const SERVER_DIR = process.env.SERVER_DIR || '/home/innotex/Documents/Projet/Serveur NationsGlory/NationsGlory_ServeurBuild_Red';
 
 async function initUsersFile() {
   await fs.ensureDir(path.dirname(USERS_FILE));

backend/src/routes/backup.js

@@ -2,9 +2,9 @@ const express = require('express');
 const fs = require('fs-extra');
 const path = require('path');
 const { exec } = require('child_process');
-const { SERVER_DIR } = require('../server');
 
 const router = express.Router();
+const SERVER_DIR = process.env.SERVER_DIR || '/home/innotex/Documents/Projet/Serveur NationsGlory/NationsGlory_ServeurBuild_Red';
 
 function isAuthenticated(req, res, next) {
   if (req.session.user) {

backend/src/routes/logs.js

@@ -1,9 +1,9 @@
 const express = require('express');
 const fs = require('fs-extra');
 const path = require('path');
-const { SERVER_DIR } = require('../server');
 
 const router = express.Router();
+const SERVER_DIR = process.env.SERVER_DIR || '/home/innotex/Documents/Projet/Serveur NationsGlory/NationsGlory_ServeurBuild_Red';
 
 function isAuthenticated(req, res, next) {
   if (req.session.user) {

backend/src/routes/players.js

@@ -1,9 +1,9 @@
 const express = require('express');
 const fs = require('fs-extra');
 const path = require('path');
-const { SERVER_DIR } = require('../server');
 
 const router = express.Router();
+const SERVER_DIR = process.env.SERVER_DIR || '/home/innotex/Documents/Projet/Serveur NationsGlory/NationsGlory_ServeurBuild_Red';
 
 function isAuthenticated(req, res, next) {
   if (req.session.user) {

backend/src/routes/rcon.js

@@ -2,9 +2,9 @@ const express = require('express');
 const RconClient = require('../utils/rcon');
 const fs = require('fs-extra');
 const path = require('path');
-const { SERVER_DIR } = require('../server');
 
 const router = express.Router();
+const SERVER_DIR = process.env.SERVER_DIR || '/home/innotex/Documents/Projet/Serveur NationsGlory/NationsGlory_ServeurBuild_Red';
 
 function isAuthenticated(req, res, next) {
   if (req.session.user) {

backend/src/routes/server.js

@@ -1,9 +1,9 @@
 const express = require('express');
 const fs = require('fs-extra');
 const path = require('path');
-const { SERVER_DIR } = require('../server');
 
 const router = express.Router();
+const SERVER_DIR = process.env.SERVER_DIR || '/home/innotex/Documents/Projet/Serveur NationsGlory/NationsGlory_ServeurBuild_Red';
 
 function isAuthenticated(req, res, next) {
   if (req.session.user) {

backend/src/routes/whitelist.js

@@ -1,9 +1,9 @@
 const express = require('express');
 const fs = require('fs-extra');
 const path = require('path');
-const { SERVER_DIR } = require('../server');
 
 const router = express.Router();
+const SERVER_DIR = process.env.SERVER_DIR || '/home/innotex/Documents/Projet/Serveur NationsGlory/NationsGlory_ServeurBuild_Red';
 
 function isAuthenticated(req, res, next) {
   if (req.session.user) {

backend/src/server.js

@@ -54,11 +54,24 @@ app.get('/api/health', (req, res) => {
   res.json({ status: 'ok', timestamp: new Date() });
 });
 
-// Erreur 404
-app.use((req, res) => {
+// Servir les fichiers statiques du frontend
+app.use(express.static(path.join(__dirname, '../../frontend/public')));
+
+// Route pour l'index
+app.get('/', (req, res) => {
+  res.sendFile(path.join(__dirname, '../../frontend/public/index.html'));
+});
+
+// Erreur 404 pour les routes API non trouvées
+app.use('/api/*', (req, res) => {
   res.status(404).json({ error: 'Route non trouvée' });
 });
 
+// Pour toutes les autres routes, servir index.html (SPA support)
+app.get('*', (req, res) => {
+  res.sendFile(path.join(__dirname, '../../frontend/public/index.html'));
+});
+
 // Error handler
 app.use((err, req, res, next) => {
   console.error(err);