Apply Rector fix

[overclokk]

Description

This pull request introduces a series of refactors aimed at improving the consistency, clarity, and maintainability of the codebase. Key changes include:

• Docker Setup: Improved host user and group mappings, enhanced permissions management, and aligned code execution with the www-data user.
• Class Aliasing: Updated logic to ensure aliases are conditionally created only when the target class does not already exist.
• Rector Configuration: Simplified rules, enabled unused import removal, and enhanced coding styles.
• Imports and Classes: Simplified imports and class declarations, removed unused imports, and replaced fully qualified names with use statements for better clarity.
• Test Improvements: Updated test assertions for stricter type checks, declared all test classes as final for consistency, and removed unused test methods.
• Keyword Usage: Added readonly keyword where applicable and enforced consistency by marking relevant classes as final and readonly.
• Dependencies and Config: Updated phpstan and rector dependencies, cleaned up Rector configurations, and streamlined the codebase by removing redundant code.
• Unit Test Bootstrap: Introduced a bootstrap to facilitate testing of final classes.

Checklist

• Tests have been added/updated where necessary.
• Documentation has been updated (if applicable).
• Code adheres to the coding standards.
• Changes have been tested and verified.