* refactor(ui): remove unused helpers and share provider selection

Remove four uncalled QML helpers and migrate tests to active label adapters. Move the shared selection transition into ProviderOrder while retaining Overview policy and covering immutable inputs and alias limits.

Documentation: update Development ownership and verification notes. Usage, README, translations, changelog and TODO are unaffected because behavior, persisted configuration and Linux parity are unchanged.

* chore(i18n): refresh catalog references after helper removal

Regenerate the POT template with make translations. Only source references change; messages and translations are unchanged.