CATROID-1662 Let user revert project deletion

[hannesweilharter]

Currently, when a user accidentially deletes a project, there is no way to recover the deleted project.
This PR introduces an undo functionality for project deletions. They are tracked and can be reverted with an undo-button in the top menu bar, similar to the one that already exists for modifications inside a project or in the backpack. Initially only the last deleted project is tracked and can be reverted.

Implementation Details

• Before a project is deleted, its entire directory is copied into a dedicated hidden backup location (PROJECT_DELETION_UNDO_DIRECTORY).
• If the backup is created successfully, the original project is deleted as usual.
• The UI displays an Undoaction whenever a valid backup exists.
• Selecting Undo restores the project by copying the backup back into the projects directory.
• If another project with the same name already exists, a unique project name is generated automatically, and the project's metadata (code.xml) is updated accordingly.
• After a successful restore, the temporary backup is removed and the Undo option is hidden.

Testcases
added in DeleteProjectTest.java:

• deleteProjectShowUndoButtonTest
• undoDeletedProjectTest
• undoOptionNotVisibleAfterActivityChangeTest

https://catrobat.atlassian.net/browse/CATROID-1662

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[sonarqubecloud]

Quality Gate passed

Issues
1 New issue
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud