refactor(notifications): extract provider message presentation (#456)

Preserve provider notification wording, urgency, dispatch ordering and privacy. Use a localized retained-usage assertion in the runtime smoke.

Published through the Git data API after Git push transport failures. The tree exactly matches local verified commit 91a311d20c0502608caf70cabf7aad91a53d82ae. Ownership documentation and gettext references are updated; supported behavior and TODO are unchanged.
f0be94213bSimone committed on 10/7/2026, 6:22:23 PM· committed by GitHubparent377ce7d
9 files changedLine totals unavailable