Fix duplicate data-index values in property editor add/save handlers

[Copilot]

The "Add Condition/Validation/Dependency" click handlers captured the array .length at listener-registration time as the new row's data-index. After any add or delete, subsequent clicks produced duplicate indices, causing save-time lookups to read the wrong row's data.

Changes

• Click handlers — compute the next index at click time by counting current .card elements in the container instead of closing over the stale array length:

  btnAdd.addEventListener('click', () => {
      const nextIndex = container.querySelectorAll('.card').length;
      this.addConditionRow({}, nextIndex);
  });

• Save-time loops — replace the forEach enumeration index with el.dataset.index so lookups match the actual data-index attribute on each row, regardless of insertion/deletion history:

  document.querySelectorAll('.condition-field').forEach((el) => {
      const index = el.dataset.index;  // was: forEach counter
      const operator = document.querySelector(`.condition-operator[data-index="${index}"]`).value;
      ...
  });

Affects all three tabs: Conditional Logic, Validation Rules, and Dependencies.

[Copilot]

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[Copilot]

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[matteius]

@copilot resolve the merge conflicts in this pull request

[Copilot]

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[Copilot]

@copilot resolve the merge conflicts in this pull request

Resolved. Merged main into the branch — the four conflicted files (form-builder-property-editor.js, form-builder.js, and two test files) are now reconciled, with the bug fixes from this PR applied on top of the latest main. All 109 tests pass.