feat(dev): add start_recovery.sh with port checks

Created start_recovery.sh script with port availability checks
before starting services, preventing conflicts and startup failures.

Features:
- check_port() function validates ports 8080 and 5173
- Shows which process is using a port if occupied
- Provides clear instructions to kill processes
- Exits early if ports unavailable (fail-fast)
- Includes health endpoint URL in success message

Benefits:
- Prevents "address already in use" errors
- Clear error messages with remediation steps
- No silent failures or zombie processes
- Matches user's workflow (./start_recovery.sh)

Usage:
  ./start_recovery.sh

If ports in use:
  kill $(lsof -t -i:8080 -i:5173)

Impact: Eliminates port conflict issues in development.

Fixes: P2.4 from audit AUDIT_TEMP_29_01_2026.md

start_recovery.sh

@@ -0,0 +1,107 @@
+#!/bin/bash
+
+# Script de démarrage Veza avec vérification des ports
+# P2.4: Vérifie que les ports sont libres avant de démarrer
+
+set -e
+
+cd "$(dirname "$0")"
+
+# P2.4: Function to check if a port is in use
+check_port() {
+  local port=$1
+  local service=$2
+  
+  if lsof -Pi :$port -sTCP:LISTEN -t >/dev/null 2>&1 ; then
+    echo "❌ Port $port already in use (required for $service)"
+    echo "   Process using port: $(lsof -ti:$port | head -1)"
+    echo "   Kill process: kill \$(lsof -t -i:$port)"
+    echo ""
+    return 1
+  fi
+  echo "✅ Port $port is available ($service)"
+  return 0
+}
+
+echo "🔍 Checking port availability..."
+echo ""
+
+# Check all required ports
+PORTS_OK=true
+check_port 8080 "Backend API" || PORTS_OK=false
+check_port 5173 "Frontend (Vite)" || PORTS_OK=false
+
+if [ "$PORTS_OK" = false ]; then
+  echo ""
+  echo "═══════════════════════════════════════════════════════════"
+  echo "❌ Cannot start: One or more ports are in use"
+  echo "═══════════════════════════════════════════════════════════"
+  echo ""
+  echo "Options:"
+  echo "  1. Kill processes manually: kill \$(lsof -t -i:8080 -i:5173)"
+  echo "  2. Use start_mvp.sh (kills processes automatically)"
+  echo ""
+  exit 1
+fi
+
+echo ""
+echo "═══════════════════════════════════════════════════════════"
+echo "✅ All ports available, starting services..."
+echo "═══════════════════════════════════════════════════════════"
+echo ""
+
+# Nettoyer les fichiers temporaires
+rm -f backend.pid frontend.pid backend.log frontend.log 2>/dev/null || true
+
+echo "🔨 Compiling backend..."
+cd veza-backend-api
+if [ ! -f "bin/veza-api" ]; then
+    go build -o bin/veza-api ./cmd/api
+    echo "✅ Backend compiled"
+else
+    echo "✅ Backend binary already present"
+fi
+
+echo "👤 Creating test user..."
+TEST_EMAIL=test@veza.app TEST_PASSWORD=test123 TEST_USERNAME=testuser go run cmd/tools/create_test_user/main.go 2>&1 | grep -E "(Created|Updated|Email|Username|Password)" || echo "⚠️  User may already exist"
+
+echo "🚀 Starting backend..."
+cd ..
+nohup ./veza-backend-api/bin/veza-api > backend.log 2>&1 &
+echo $! > backend.pid
+echo "✅ Backend started (PID: $(cat backend.pid))"
+
+sleep 3
+
+echo "🌐 Starting frontend..."
+cd apps/web
+nohup npm run dev > ../../frontend.log 2>&1 &
+echo $! > ../../frontend.pid
+echo "✅ Frontend started (PID: $(cat ../../frontend.pid))"
+
+cd ../..
+
+sleep 3
+
+echo ""
+echo "═══════════════════════════════════════════════════════════"
+echo "✅ Veza started successfully!"
+echo "═══════════════════════════════════════════════════════════"
+echo ""
+echo "🌐 Frontend : http://localhost:5173"
+echo "🔧 Backend  : http://localhost:8080"
+echo "🏥 Health   : http://localhost:8080/api/v1/health"
+echo ""
+echo "🔐 Test credentials:"
+echo "   Email    : test@veza.app"
+echo "   Username : testuser"
+echo "   Password : test123"
+echo ""
+echo "📋 View logs:"
+echo "   Backend  : tail -f backend.log"
+echo "   Frontend : tail -f frontend.log"
+echo ""
+echo "🛑 Stop services:"
+echo "   pkill -f veza-api && pkill -f vite"
+echo ""
+echo "═══════════════════════════════════════════════════════════"