📄 Update license to 2026 (#903)

## Description

This PR updates the license file to 2026.

## Checklist:

- [x] The pull request only contains commits that are focused and
relevant to this change.
- [x] ~I have added appropriate tests that cover the new/changed
functionality.~
- [x] ~I have updated the documentation to reflect these changes.~
- [x] ~I have added entries to the changelog for any noteworthy
additions, changes, fixes, or removals.~
- [x] ~I have added migration instructions to the upgrade guide (if
needed).~
- [x] The changes follow the project's style guidelines and introduce no
new warnings.
- [x] The changes are fully tested and pass the CI checks.
- [x] I have reviewed my own code changes.

Author: denialhaag

LICENSE.md

@@ -1,7 +1,7 @@
 MIT License
 
-Copyright (c) 2023 - 2025 Chair for Design Automation, TUM
-Copyright (c) 2025 Munich Quantum Software Company GmbH
+Copyright (c) 2023 - 2026 Chair for Design Automation, TUM
+Copyright (c) 2025 - 2026 Munich Quantum Software Company GmbH
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal