Add API endpoints and management pages for software versions and upgrade paths

- Implemented API endpoint for managing software versions in `products_software_versions.php`.
- Created management page for software version assignments in `products_software_assignments.php`.
- Developed upgrade paths management functionality in `products_software_upgrade_paths_manage.php`.
- Enhanced software version details page in `products_software_version.php`.
- Added form handling and validation for software version creation and updates in `products_software_version_manage.php`.
- Introduced pagination and filtering for software versions in `products_software_versions.php`.
- Implemented success message handling for CRUD operations across various pages.

settings/settingsmenu.php

@@ -142,6 +142,12 @@ $main_menu = [
             "selected" => "products", 
             "icon" => "fas fa-box-open",
             "name" => "menu_products"  
+            ],
+        "products_software" => [
+            "url" => "products_software_versions", 
+            "selected" => "products_software_versions", 
+            "icon" => "fas fa-box-open",
+            "name" => "menu_products_software_versions"  
             ], 
         "products_attributes" => [
             "url" => "products_attributes", 
@@ -281,14 +287,6 @@ $main_menu = [
             "icon" => "fas fa-tachometer-alt",
             "name" => "menu_profiles"  
         ]
-    ],
-    "upgrades" => [
-        "main_menu" => [
-            "url" => "upgrades",
-            "selected" => "upgrades",
-            "icon" => "fas fa-download",
-            "name" => "menu_upgrades"
-        ]
     ]
 ];
 
@@ -324,6 +322,8 @@ $page_rows_shipping = 25;//discounts
 $page_rows_transactions = 25; //transactions
 $page_rows_invoice = 25; //invoices
 $page_rows_dealers = 25; //dealers
+$page_rows_software_versions = 50; //software versions
+$page_rows_software_assignment = 50; //software assignment
 
 //------------------------------------------
 // Languages supported