Update Magento 2 Module (Transiteo) for PHP 8.1 / Magento 2.4.7 Compatibility

Context
We are Transiteo, provider of a landed cost and regulatory compliance module for international e-commerce.
Our module was initially developed for Magento 2.4.x and PHP 7.4, and now requires an upgrade to ensure full compatibility with:
- PHP 8.1 or 8.2
- Magento 2.4.7

The module integrates:
- International duties and tax calculation logic
- Product and order synchronization

Goals
- Ensure compatibility with PHP 8.1 and 8.2
- Ensure compatibility with Magento 2.4.7 (framework version 103.0+)
- Refactor deprecated or incompatible code
- Test and validate the module on a staging environment

Key Tasks
*Code Upgrade & Refactoring
- Update composer.json to reflect new PHP version requirements
- Replace deprecated PHP functions (e.g., each(), create_function())
- Update Reflection usage (e.g., getClass() → getType())
- Apply strict typing where needed
- Ensure compatibility of Magento DI and XML declarations

*Testing & Debugging
- Enable Developer Mode
- Run bin/magento setup:di:compile and setup:upgrade
- Test custom module logic:
- - Product & order synchronization
- - API calls for tax data

*Compatibility Check
- Analyze current use of Zend/Laminas packages
- Ensure PSR-compliant logging (LoggerInterface)
- Validate observers, plugins and CLI commands if present

*Skills Required
Expert in Magento 2 module development
Deep understanding of PHP 8.1+ migration best practices
Comfortable working with complex business logic modules
Bonus: Experience with headless Magento / GraphQL

*Deliverables
Fully working module compatible with Magento 2.4.7
PHP 8.1 or 8.2 compatibility confirmed
All breaking changes documented
Source code in Git repository (private or zip delivery)

* Provided
- Current module source code (ZIP)
- Magento 2.4.7 staging environment available
- Technical contact for coordination & support