RuleModeSwitcher rebuilt a rule's actions from scratch, so changing the
mode of e.g. .m.rule.is_user_mention silently dropped its highlight tweak
account-wide. Derive the existing highlight/custom-sound tweaks from the
rule's current actions and pass them through as NotificationModeOptions.
Adds getNotificationModeOptionsFromActions + unit tests.
Fixes#19
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PPmy3tPq869XDW4njjVaKA