Implement PM mode optimization (STATIC/DYNAMIC/ONDEMAND) for Option 4

- Add apply_pm_mode selection logic
- Display PM mode as separate option (option 2) in optimization menu
- Apply pm, pm.min_spare_servers, and pm.max_spare_servers settings
- Uses improved algorithm recommendations for DYNAMIC/ONDEMAND modes
- Includes min_spare and max_spare configuration for non-STATIC modes
- Now applies full set of recommendations from calculator, not just max_children

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

modules/performance/php-optimizer.sh

@@ -535,7 +535,8 @@ optimize_domain() {
     echo ""
     cecho "  ${GREEN}a${NC}) Apply all $opt_count recommendations"
     [ "${opt_available[max_children]}" = "true" ] && cecho "  ${GREEN}1${NC}) Apply max_children optimization only"
-    [ "${opt_available[opcache]}" = "true" ] && cecho "  ${GREEN}2${NC}) Apply OPcache optimization only"
+    [ "${opt_available[pm_mode]}" = "true" ] && cecho "  ${GREEN}2${NC}) Apply PM mode optimization only"
+    [ "${opt_available[opcache]}" = "true" ] && cecho "  ${GREEN}3${NC}) Apply OPcache optimization only"
     cecho "  ${RED}n${NC}) Cancel - don't apply any changes"
     echo ""
     cecho "${CYAN}─────────────────────────────────────────────────────────────────────${NC}"
@@ -544,9 +545,9 @@ optimize_domain() {
     while true; do
         read -p "Select option: " apply_choice
 
-        if ! [[ "$apply_choice" =~ ^[a1A2nN]$ ]]; then
+        if ! [[ "$apply_choice" =~ ^[a123nNA]$ ]]; then
             echo ""
-            cecho "${RED}Invalid selection. Please enter a, 1, 2, or n${NC}"
+            cecho "${RED}Invalid selection. Please enter a, 1, 2, 3, or n${NC}"
             echo ""
             continue
         fi
@@ -555,6 +556,7 @@ optimize_domain() {
 
     # Determine which optimizations to apply
     local apply_max_children=false
+    local apply_pm_mode=false
     local apply_opcache=false
 
     # Convert to lowercase for consistent case matching
@@ -563,12 +565,16 @@ optimize_domain() {
     case "$apply_choice" in
         a)
             apply_max_children=${opt_available[max_children]:-false}
+            apply_pm_mode=${opt_available[pm_mode]:-false}
             apply_opcache=${opt_available[opcache]:-false}
             ;;
         1)
             apply_max_children=${opt_available[max_children]:-false}
             ;;
         2)
+            apply_pm_mode=${opt_available[pm_mode]:-false}
+            ;;
+        3)
             apply_opcache=${opt_available[opcache]:-false}
             ;;
         n)
@@ -580,7 +586,7 @@ optimize_domain() {
     esac
 
     # Check if nothing was selected
-    if [ "$apply_max_children" = "false" ] && [ "$apply_opcache" = "false" ]; then
+    if [ "$apply_max_children" = "false" ] && [ "$apply_pm_mode" = "false" ] && [ "$apply_opcache" = "false" ]; then
         cecho "${YELLOW}No optimizations selected${NC}"
         echo ""
         read -p "Press Enter to continue..."
@@ -624,6 +630,34 @@ optimize_domain() {
         fi
     fi
 
+    # Apply PM mode if selected (STATIC/DYNAMIC/ONDEMAND)
+    if [ "$apply_pm_mode" = "true" ]; then
+        if [ -n "$pool_config" ] && [ -f "$pool_config" ]; then
+            if [ -n "$improved_pm_mode" ]; then
+                # Apply pm mode
+                if modify_fpm_pool_setting "$pool_config" "pm" "$improved_pm_mode" >/dev/null 2>&1; then
+                    cecho "  ${GREEN}✓${NC} Set pm = $improved_pm_mode"
+
+                    # For DYNAMIC and ONDEMAND modes, also set min/max spare servers
+                    if [[ "$improved_pm_mode" == "dynamic" ]] || [[ "$improved_pm_mode" == "ondemand" ]]; then
+                        if modify_fpm_pool_setting "$pool_config" "pm.min_spare_servers" "$improved_min_spare" >/dev/null 2>&1; then
+                            cecho "  ${GREEN}✓${NC} Set pm.min_spare_servers = $improved_min_spare"
+                        fi
+
+                        if modify_fpm_pool_setting "$pool_config" "pm.max_spare_servers" "$improved_max_spare" >/dev/null 2>&1; then
+                            cecho "  ${GREEN}✓${NC} Set pm.max_spare_servers = $improved_max_spare"
+                        fi
+                    fi
+
+                    changes_made=$((changes_made + 1))
+                else
+                    cecho "  ${RED}✗${NC} Failed to set pm mode"
+                    changes_failed=$((changes_failed + 1))
+                fi
+            fi
+        fi
+    fi
+
     # Apply OPcache if selected
     if [ "$apply_opcache" = "true" ]; then
         # Note: OPcache settings are in php.ini, not FPM pool config