feat: WordPress Monitor API + Site Availability Checker

- Add POST /api/wp-monitor endpoint for WP plugin data
- Add GET /api/wp-monitor for listing monitored sites
- Add checkSiteAvailability() function for HTTP health checks
- Add checkAllSitesAvailability() for batch checking
- Add /api/scripts/check-sites.ts for cron execution
- Add POST /api/monitor/check-sites for manual trigger

DeskCRM Task: #1556

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

api/scripts/check-sites.ts

@@ -0,0 +1,50 @@
+#!/usr/bin/env npx tsx
+/**
+ * Site Availability Checker Script
+ * Run via cron every 5-15 minutes to check if sites are online
+ *
+ * Usage:
+ *   npx tsx api/scripts/check-sites.ts
+ *
+ * Cron example (every 10 minutes):
+ *   */10 * * * * cd /path/to/DashDescomplicar && npx tsx api/scripts/check-sites.ts >> /var/log/check-sites.log 2>&1
+ *
+ * @author Descomplicar® | @link descomplicar.pt | @copyright 2026
+ */
+import 'dotenv/config'
+import { checkAllSitesAvailability } from '../services/monitoring.js'
+
+async function main() {
+  const startTime = Date.now()
+  console.log(`[${new Date().toISOString()}] Starting site availability check...`)
+
+  try {
+    const result = await checkAllSitesAvailability()
+
+    console.log(`[${new Date().toISOString()}] Check completed:`)
+    console.log(`  - Sites checked: ${result.checked}`)
+    console.log(`  - Up: ${result.up}`)
+    console.log(`  - Down: ${result.down}`)
+
+    // Log any down sites
+    const downSites = result.results.filter(r => !r.available)
+    if (downSites.length > 0) {
+      console.log(`  - Down sites:`)
+      for (const site of downSites) {
+        console.log(`    - ${site.name}: ${site.error || 'No response'}`)
+      }
+    }
+
+    const elapsed = Date.now() - startTime
+    console.log(`[${new Date().toISOString()}] Done in ${elapsed}ms`)
+
+    // Exit with code 1 if any sites are down (useful for alerting)
+    process.exit(downSites.length > 0 ? 1 : 0)
+
+  } catch (error) {
+    console.error(`[${new Date().toISOString()}] Error:`, error)
+    process.exit(2)
+  }
+}
+
+main()