Server-side dependency grouping combines different target states when evaluating reset behavior

Problem/Motivation

Conditional Fields combines dependencies for different target states during server-side submit handling.

A target field can legitimately have complementary states, for example:

• Visible when a checkbox is unchecked.
• Emptied when the same checkbox is checked.

Client-side states keep those rules separate. Server-side evaluation does not.

ConditionalFieldsFormHelper::evaluateDependencies() groups dependency results by AND/OR/XOR without also separating them by target state.

That causes submit-time reset handling to evaluate unrelated states together.

For example:

• visible when !checked, with reset: true
• empty when checked

With both in the AND group, saving while the checkbox is unchecked evaluates effectively as:

TRUE AND FALSE = FALSE

The target is then treated as untriggered and reset to its default value even though its Visible condition is active.

This is not reliably fixable by changing grouping. Functional coverage across all AND/OR/XOR combinations shows that configurations which preserve the value in one state can fail to reset it in the opposite state.

Steps to reproduce

1. Create a boolean Control field and a Target field with a default value.
2. Add a dependency to Target:
   • State: Visible
   • Condition: Control is unchecked
   • Grouping: AND
   • Enable "Reset the target to its default values when the form is submitted if the dependency is not triggered."
3. Add another dependency to Target:
   • State: Emptied
   • Condition: Control is checked
   • Grouping: AND
4. Leave Control unchecked.
5. Enter a non-default value in Target.
6. Save.
7. Observe that Target is reset to its default value even though its Visible condition is triggered.

Proposed resolution

Keep dependencies for different target states separate during server-side evaluation.

Submit-time reset behavior should be evaluated against the dependency or state where reset is configured. A dependency for another state such as empty should not affect whether a visible dependency is considered triggered.

Update ConditionalFieldsFormHelper::evaluateDependencies() and related reset handling so server-side behavior matches the state separation already used for client-side Drupal states.

Add functional coverage for the full AND/OR/XOR matrix across complementary visible and empty states.

Remaining tasks

• Add failing functional test coverage.
• Fix server-side dependency evaluation so target states remain separate.
• Confirm existing single-state grouping behavior remains unchanged.

User interface changes

None.

API changes

No public API changes expected.

Data model changes

None.