feat: 31 languages + disk safety panel + electron auto-updater + VM uninstall

i18n:
- Expanded from 6 to 31 languages (no Hebrew per policy)
- Added: pt, ru, ja, ko, hi, tr, it, nl, pl, sv, id, uk, th, vi, fa, cs, ms, ro, el, bn, hu, fi, da, no, ur
- RTL support for ar, fa, ur
- Language selector dropdown wired into dashboard navbar

Disk Safety:
- New backend route /api/v1/disk-settings (GET/POST/cleanup)
- Frontend modal with sliders for health interval, max entries, retention days
- Clean Up Now button triggers immediate cleanup
- Wired into dashboard navbar

Desktop Auto-Updater (from timed-out subagent):
- electron-updater installed and configured
- Checks get.dashcaddy.net/release/ for updates
- Publish config added to package.json

VM Uninstall:
- Wizard calls vmDestroy before regular uninstall
- Cleans up VM/disk sandbox on uninstall

Cleanup:
- Recursive data nesting guard (nesting-guard.js)
- Removed 242MB of data/data/data/ duplicates

dashcaddy-api/routes/disk-settings.js

@@ -0,0 +1,98 @@
+const express = require('express');
+const router = express.Router();
+const fs = require('fs');
+const path = require('path');
+
+// GET current disk settings + actual disk usage
+router.get('/', (req, res) => {
+  try {
+    const settings = {
+      healthCheckInterval: parseInt(process.env.HEALTH_CHECK_INTERVAL || '30000'),
+      healthMaxEntries: parseInt(process.env.HEALTH_MAX_ENTRIES || '500'),
+      healthRetentionDays: parseInt(process.env.HEALTH_HISTORY_RETENTION || '14'),
+      statsMaxEntries: parseInt(process.env.CONTAINER_STATS_MAX_ENTRIES || '500'),
+      auditMaxEntries: parseInt(process.env.AUDIT_MAX_ENTRIES || '1000'),
+      backupMaxStorageBytes: parseInt(process.env.BACKUP_MAX_STORAGE_BYTES || '0'),
+    };
+
+    // Get actual disk usage
+    let diskUsage = { total: 0, used: 0, free: 0, dataDirSize: 0 };
+    try {
+      const { execSync } = require('child_process');
+      const dfOut = execSync("df -B1 /opt/dashcaddy/dashcaddy-api/data 2>/dev/null || df -B1 / 2>/dev/null").toString().trim().split('\n');
+      if (dfOut.length > 1) {
+        const parts = dfOut[1].split(/\s+/);
+        diskUsage.total = parseInt(parts[1]) || 0;
+        diskUsage.used = parseInt(parts[2]) || 0;
+        diskUsage.free = parseInt(parts[3]) || 0;
+      }
+      const duOut = execSync("du -sb /opt/dashcaddy/dashcaddy-api/data 2>/dev/null || echo 0").toString().trim().split(/\s+/);
+      diskUsage.dataDirSize = parseInt(duOut[0]) || 0;
+    } catch {}
+
+    // Load persisted settings
+    const settingsFile = path.join(path.dirname(require('../config/paths').configFile), 'disk-settings.json');
+    let persisted = {};
+    try { persisted = JSON.parse(fs.readFileSync(settingsFile, 'utf8')); } catch {}
+    
+    res.json({ success: true, current: { ...settings, ...persisted }, diskUsage });
+  } catch (e) {
+    res.status(500).json({ success: false, error: e.message });
+  }
+});
+
+// POST update settings
+router.post('/', (req, res) => {
+  try {
+    const { healthInterval, healthMaxEntries, healthRetentionDays, statsMaxEntries, auditMaxEntries } = req.body;
+    const updates = {};
+    
+    if (healthInterval !== undefined) { updates.healthCheckInterval = parseInt(healthInterval); process.env.HEALTH_CHECK_INTERVAL = String(healthInterval); }
+    if (healthMaxEntries !== undefined) { updates.healthMaxEntries = parseInt(healthMaxEntries); process.env.HEALTH_MAX_ENTRIES = String(healthMaxEntries); }
+    if (healthRetentionDays !== undefined) { updates.healthRetentionDays = parseInt(healthRetentionDays); process.env.HEALTH_HISTORY_RETENTION = String(healthRetentionDays); }
+    if (statsMaxEntries !== undefined) { updates.statsMaxEntries = parseInt(statsMaxEntries); process.env.CONTAINER_STATS_MAX_ENTRIES = String(statsMaxEntries); }
+    if (auditMaxEntries !== undefined) { updates.auditMaxEntries = parseInt(auditMaxEntries); process.env.AUDIT_MAX_ENTRIES = String(auditMaxEntries); }
+    
+    // Persist to file
+    const paths = require('../config/paths');
+    const settingsFile = path.join(path.dirname(paths.configFile), 'disk-settings.json');
+    let existing = {};
+    try { existing = JSON.parse(fs.readFileSync(settingsFile, 'utf8')); } catch {}
+    fs.writeFileSync(settingsFile, JSON.stringify({ ...existing, ...updates }, null, 2));
+    
+    res.json({ success: true, updated: updates, message: 'Settings saved. Some changes apply on next container restart.' });
+  } catch (e) {
+    res.status(500).json({ success: false, error: e.message });
+  }
+});
+
+// POST trigger immediate cleanup
+router.post('/cleanup', async (req, res) => {
+  try {
+    const results = { cleaned: {} };
+    
+    // Clean health history
+    try {
+      const healthChecker = require('../monitoring/health-checker');
+      if (healthChecker.instance && healthChecker.instance.cleanupHistory) {
+        healthChecker.instance.cleanupHistory();
+        results.cleaned.healthHistory = 'Cleaned old entries';
+      }
+    } catch (e) { results.cleaned.healthHistory = 'Skipped: ' + e.message; }
+    
+    // Clean container stats
+    try {
+      const resourceMonitor = require('../managers/resource-monitor');
+      if (resourceMonitor.instance && resourceMonitor.instance.cleanupOldStats) {
+        resourceMonitor.instance.cleanupOldStats();
+        results.cleaned.containerStats = 'Cleaned old entries';
+      }
+    } catch (e) { results.cleaned.containerStats = 'Skipped: ' + e.message; }
+    
+    res.json({ success: true, results });
+  } catch (e) {
+    res.status(500).json({ success: false, error: e.message });
+  }
+});
+
+module.exports = router;