* ✨ Expand interaction helper test coverage
Add coverage for interaction destination and flow helpers,
including nil handling and removal helpers. Document the
intent of the new assertions so future interaction changes
keep the helper contract explicit.
* ✨ Cover interaction validation edge cases
Exercise the remaining interaction guards and overlay
positioning edge cases, including invalid state
transitions and nested manual offsets. Keep the test
comments focused on why each branch matters for editor
behavior.
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