fix(gui): prevent crash on right-click in Project Explorer with no selection

[bhavyabhardwaj001]

Related Issues

Closes #509

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Purpose

The Project Explorer context menu crashes when a user right-clicks without selecting any item. This happens because the current implementation relies on selectedIndexes() and assumes that a selection is always present.

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Approach

• Replaced selectedIndexes() with indexAt(position) to determine the item under the cursor
• Added index.isValid() check to safely handle right-clicks on empty areas
• Set the clicked index as the current selection to maintain expected menu behavior
• Used a temporary index (temp_index) to safely traverse parent hierarchy and compute level

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Changes Made

• Updated openMenu() implementation in ProjectExplorer.py
• Removed unsafe access to indexes[0]
• Refactored logic to depend on actual user interaction instead of prior selection state
• Ensured level is always initialized before use

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Impact

• Prevents application crash on right-click with no selection
• Improves robustness and consistency of context menu behavior
• Maintains existing functionality for valid selections

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Verification

• Right-click on empty space → no crash, no unintended behavior
• Right-click on project/file → context menu opens correctly
• Right-click on nested items → correct level detection and menu behavior