CATROID-1657 Fix SpriteActivity Undo-Handling after App Crash

[herbsee02]

This PR refactors the Undo-Handling of SpriteActivity after an app crash, resolving several UI synchronization bugs and lifecycle inconsistencies.

https://catrobat.atlassian.net/browse/CATROID-1657

• Crash Recovery: Implemented a new system to restore the Undo button and its navigation context (Scene/Sprite) after an app crash or OS process kill. Therefore, the existing system (introduced in IDE-309) where the SpriteActivity was kept alive with an inconsistent state in BaseActivity was removed, as it led to the initial Null-Pointer-Exception in createActionBarTitle.
• Centralized Reset: Moved the Undo state reset logic to the central loadFragment method, ensuring a clean UI when switching between Scripts, Looks, and Sounds.
• Architecture Cleanup: Standardized menu updates using invalidateOptionsMenu() and removed redundant cleanup code from individual fragments.
• Bug Fixes:
  • Resolved a ClassCastException when editing non-string variables.
  • Fixed a bug where the Undo button persisted after canceled drawing sessions.
  • Changed Espresso UI tests.

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
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

[sonarqubecloud]

Quality Gate passed

Issues
2 New issues
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

[hannesweilharter]

thanks!