Use FVM in GitHub Actions and migrate to Flutter 3.32.4 (#641)

* feat: implement Flutter version management using FVM across CI workflows

* Flutter 3.29.3 + minor Package upgrades

* Replace deprecated `withOpacity`

* Upgrade major package versions without breaking changes.

* Disable unnecessary_async rule

Re-enable later

* New language version and automated fixes

- unnecessary_breaks
- unnecessary_underscore

* Update BUILDING.md to use fvm commands

* Add gitignore files for Android and iOS build artifacts

* Migrate iOS dependencies to Swift Package Manager

This is being done automatically by Flutter

* Flutter 3.32.4

* New sdk version

* docs: add IDE setup instructions and troubleshooting guide for FVM integration

lib/inventree/model.dart

@@ -584,7 +584,6 @@ class InvenTreeModel {
             L10().itemDeleted,
             success: false,
           );
-          break;
         default:
           String detail = L10().errorFetch;
           detail += "\n${L10().statusCode}: ${response.statusCode}";
@@ -594,7 +593,6 @@ class InvenTreeModel {
               L10().serverError,
               detail
           );
-          break;
       }
 
       return false;