Fix - Visibility conditions not working on tree cascade dropdown questions

[RomainLvr]

Checklist before requesting a review

Please delete options that are not relevant.

• I have performed a self-review of my code.
• I have added tests (when available) that prove my fix is effective or that my feature works.
• I have updated the CHANGELOG with a short functional description of the fix or new feature.
• This change requires a documentation update.

Description

• It fixes !44659
• Here is a brief description of what this PR does

ItemAsTextConditionHandler uses getName() which returns only the item's own name. For tree dropdowns, a child item's name does not include its ancestors, so a condition like "contains Parent" always failed. Fixed by introducing TreeCascadeItemAsTextConditionHandler in the plugin, which uses completename ("Parent > Child") for CommonTreeDropdown items. TreeCascadeDropdownQuestion::getConditionHandlers() is overridden to substitute this handler.

[RomainLvr]

I have the customer test it

[stonebuzz]

The else branch ($text = $item->getName()) is dead code. This class is only ever constructed in TreeCascadeDropdownQuestion::getConditionHandlers(), which itself is only reachable for CommonTreeDropdown itemtypes

Suggested change

	if ($item instanceof CommonTreeDropdown) {
	$completename = $item->fields['completename'];
	$text = is_string($completename) ? $completename : '';
	} else {
	$text = $item->getName();
	}
	// Use completename for tree dropdowns so that conditions referencing
	// ancestor nodes match correctly (e.g. "contains Parent" matches a child
	// whose completename is "Parent > Child").
	$completename = $item->fields['completename'] ?? '';
	$text = is_string($completename) ? $completename : '';

[stonebuzz]

Can you add a test case where the parent item itself is selected (not a child), confirming that CONTAINS 'Parent Location' still matches when completename = 'Parent Location'? The two existing tests only cover a child item; the root-level selection path is untested.

[stonebuzz]

Can you add a test case where no item is selected (items_id = 0)? applyValueOperator returns false for both operators in that case, which means a NOT_CONTAINS X condition evaluates to false (dependent question hidden) when nothing is selected. This is non-obvious behavior and worth pinning with a test.