fix: remove HEAD-based site checker that caused false DOWN status

The checkAllSitesAvailability() function did HEAD requests from EasyPanel
to check sites. Many WordPress sites block HEAD or return errors, causing
all sites to show as DOWN while keeping valid response times from the
CWP collector. The CWP collector (collect-sites.sh) is the single source
of truth for site status.

Removed:
- checkSiteAvailability() and checkAllSitesAvailability() from monitoring service
- POST /api/monitor/check-sites endpoint
- api/scripts/check-sites.ts cron script

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

api/services/monitoring.ts

@@ -9,12 +9,9 @@ interface MonitoringItem {
   id: number
   name: string
   category: string
-  type: string
   status: string
   details: any
   last_check: string
-  created_at: string
-  updated_at: string
 }
 
 interface CategorySummary {
@@ -25,105 +22,6 @@ interface CategorySummary {
   critical: number
 }
 
-/**
- * Check if a URL is accessible (HTTP HEAD request)
- */
-export async function checkSiteAvailability(url: string, timeout = 10000): Promise<{
-  available: boolean
-  statusCode?: number
-  responseTime?: number
-  error?: string
-}> {
-  const startTime = Date.now()
-  const controller = new AbortController()
-  const timeoutId = setTimeout(() => controller.abort(), timeout)
-
-  try {
-    const response = await fetch(url, {
-      method: 'HEAD',
-      signal: controller.signal,
-      headers: {
-        'User-Agent': 'Descomplicar-Monitor/1.0'
-      }
-    })
-
-    clearTimeout(timeoutId)
-    const responseTime = Date.now() - startTime
-
-    return {
-      available: response.ok || response.status < 500,
-      statusCode: response.status,
-      responseTime
-    }
-  } catch (error) {
-    clearTimeout(timeoutId)
-    return {
-      available: false,
-      error: (error as Error).message,
-      responseTime: Date.now() - startTime
-    }
-  }
-}
-
-/**
- * Check all sites and update their availability status
- */
-export async function checkAllSitesAvailability(): Promise<{
-  checked: number
-  up: number
-  down: number
-  results: any[]
-}> {
-  // Get all sites from monitoring table
-  const [sites] = await db.query<RowDataPacket[]>(`
-    SELECT id, name, details FROM tbl_eal_monitoring
-    WHERE category = 'site'
-  `)
-
-  const results: any[] = []
-  let up = 0
-  let down = 0
-
-  for (const site of sites) {
-    const details = typeof site.details === 'string' ? JSON.parse(site.details) : site.details
-    const siteUrl = details?.site_url || `https://${site.name}`
-
-    const check = await checkSiteAvailability(siteUrl)
-
-    // Update status if site is down
-    if (!check.available) {
-      await db.query(
-        'UPDATE tbl_eal_monitoring SET status = ?, last_check = NOW() WHERE id = ?',
-        ['down', site.id]
-      )
-      down++
-    } else {
-      // If was down and now is up, set to 'up' (will be replaced by plugin data later)
-      const currentStatus = details?.health?.status || 'ok'
-      if (currentStatus === 'down') {
-        await db.query(
-          'UPDATE tbl_eal_monitoring SET status = ?, last_check = NOW() WHERE id = ?',
-          ['up', site.id]
-        )
-      }
-      up++
-    }
-
-    results.push({
-      name: site.name,
-      url: siteUrl,
-      ...check
-    })
-  }
-
-  return {
-    checked: sites.length,
-    up,
-    down,
-    results
-  }
-}
-
 export async function getMonitoringData() {
   // Get all items
   const [items] = await db.query<RowDataPacket[]>(`