Add modular server update feature with Discord notifications

- Add serverUpdates.js service with handler registry for extensibility
- Implement Factorio Docker image update (pull + container recreate)
- Add GET/POST /servers/:id/update routes for check/perform
- Add ServerUpdateButton component with auto-check and confirm dialog
- Integrate update card in ServerDetail overview tab
- Auto-send Discord notification on successful update

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

gsm-backend/routes/servers.js

@@ -5,6 +5,7 @@ import { fileURLToPath } from 'url';
 import { EmbedBuilder } from 'discord.js';
 import { authenticateToken, optionalAuth, requireRole, rejectGuest } from '../middleware/auth.js';
 import { getServerStatus, startServer, stopServer, restartServer, getConsoleLog, getProcessUptime, listFactorioSaves, createFactorioWorld, deleteFactorioSave, getFactorioCurrentSave, isHostFailed, listZomboidConfigs, readZomboidConfig, writeZomboidConfig, listPalworldConfigs, readPalworldConfig, writePalworldConfig, readTerrariaConfig, writeTerrariaConfig, readOpenTTDConfig, writeOpenTTDConfig, readHytaleConfig, writeHytaleConfig } from '../services/ssh.js';
+import { supportsUpdate, checkForUpdate, performUpdate } from '../services/serverUpdates.js';
 import { sendRconCommand, getPlayers, getPlayerList } from '../services/rcon.js';
 import { getServerMetricsHistory, getCurrentMetrics } from '../services/prometheus.js';
 import { initWhitelistCache, getCachedWhitelist, setCachedWhitelist, initFactorioTemplates, getFactorioTemplates, createFactorioTemplate, deleteFactorioTemplate, initFactorioWorldSettings, getFactorioWorldSettings, saveFactorioWorldSettings, deleteFactorioWorldSettings, initAutoShutdownSettings, getAutoShutdownSettings, setAutoShutdownSettings, initActivityLog, logActivity, getActivityLog, initServerDisplaySettings, getServerDisplaySettings, getAllServerDisplaySettings, setServerDisplaySettings, initGuildSettings } from '../db/init.js';
@@ -749,6 +750,75 @@ router.post('/:id/restart', authenticateToken, requireRole('moderator'), async (
   }
 });
 
+// ============ SERVER UPDATE ROUTES ============
+
+// Check for server updates (moderator+)
+router.get('/:id/update', authenticateToken, requireRole('moderator'), async (req, res) => {
+  const config = loadConfig();
+  const server = config.servers.find(s => s.id === req.params.id);
+  if (!server) return res.status(404).json({ error: 'Server not found' });
+
+  // Check if this server type supports updates
+  if (!supportsUpdate(server.type)) {
+    return res.json({
+      supported: false,
+      hasUpdate: false,
+      message: 'Updates für diesen Servertyp nicht unterstützt'
+    });
+  }
+
+  if (isHostFailed(server.host, server.sshUser)) {
+    return res.status(503).json({ error: 'Server host is unreachable', unreachable: true });
+  }
+
+  try {
+    const result = await checkForUpdate(server);
+    res.json(result);
+  } catch (err) {
+    if (err.message.includes('unreachable') || err.message.includes('ECONNREFUSED') || err.message.includes('ETIMEDOUT')) {
+      return res.status(503).json({ error: 'Server host is unreachable', unreachable: true });
+    }
+    res.status(500).json({ error: err.message });
+  }
+});
+
+// Perform server update (moderator+)
+router.post('/:id/update', authenticateToken, requireRole('moderator'), async (req, res) => {
+  const config = loadConfig();
+  const server = config.servers.find(s => s.id === req.params.id);
+  if (!server) return res.status(404).json({ error: 'Server not found' });
+
+  if (!supportsUpdate(server.type)) {
+    return res.status(400).json({ error: 'Updates für diesen Servertyp nicht unterstützt' });
+  }
+
+  if (isHostFailed(server.host, server.sshUser)) {
+    return res.status(503).json({ error: 'Server host is unreachable', unreachable: true });
+  }
+
+  // Check if server is running
+  try {
+    const status = await getServerStatus(server);
+    if (status === 'online' || status === 'starting') {
+      return res.status(400).json({ error: 'Server muss gestoppt sein um zu updaten' });
+    }
+  } catch (err) {
+    // Continue if status check fails
+  }
+
+  try {
+    const sendDiscord = req.body?.sendDiscord !== false; // Default true
+    const result = await performUpdate(server, sendDiscord);
+    logActivity(req.user.id, req.user.username, 'server_update', server.id, result.newVersion || 'latest', req.user.discordId, req.user.avatar);
+    res.json(result);
+  } catch (err) {
+    if (err.message.includes('unreachable') || err.message.includes('ECONNREFUSED') || err.message.includes('ETIMEDOUT')) {
+      return res.status(503).json({ error: 'Server host is unreachable', unreachable: true });
+    }
+    res.status(500).json({ error: err.message });
+  }
+});
+
 // Get whitelist (with server-side caching, guests not allowed)
 router.get('/:id/whitelist', authenticateToken, rejectGuest, async (req, res) => {
   const config = loadConfig();