Rename Performance Analysis to Performance & Maintenance

The menu now includes both performance analysis tools (MySQL Query
Analyzer, Network & Bandwidth, Hardware Health, PHP Optimizer) and
system maintenance tools (Disk Space Analyzer, Loadwatch).

Changes:
- Main menu: "Performance Analysis" → "Performance & Maintenance"
- Submenu title: "🔧 Performance Analysis" → "🔧 Performance & Maintenance"

This better reflects the dual purpose of the menu category.

launcher.sh

@@ -91,7 +91,7 @@ show_main_menu() {
     echo ""
     echo -e "  ${GREEN}2)${NC} 🛡️  Security & Monitoring"
     echo -e "  ${BLUE}3)${NC} 🌐 Website Diagnostics"
-    echo -e "  ${MAGENTA}4)${NC} 🔧 Performance Analysis"
+    echo -e "  ${MAGENTA}4)${NC} 🔧 Performance & Maintenance"
     echo -e "  ${YELLOW}5)${NC} 💾 Backup & Recovery"
     echo ""
     echo -e "${BOLD}System:${NC}"
@@ -221,7 +221,7 @@ handle_website_menu() {
 
 show_performance_menu() {
     show_banner
-    echo -e "${MAGENTA}${BOLD}🔧 Performance Analysis${NC}"
+    echo -e "${MAGENTA}${BOLD}🔧 Performance & Maintenance${NC}"
     echo ""
     echo -e "${BOLD}Database:${NC}"
     echo ""