Gate WebSocket toast notifications by per-feature popup settings

[boomzero]

What does this PR aim to accomplish?:

The WebSocket notification handler (HandleNotificationMessage) dispatches bbs_mention and mail_mention toasts unconditionally, bypassing the user's BBSPopup / MessagePopup toggle settings. The polling fallback (PollNotifications) already gates each toast type with UtilityEnabled(), so behavior differs depending on connection state — users who disabled a notification type still receive those toasts over WebSocket.

How does this PR accomplish the above?:

Wraps the CreateAndShowBBSMentionToast and CreateAndShowMailMentionToast calls in HandleNotificationMessage with UtilityEnabled("BBSPopup") and UtilityEnabled("MessagePopup") checks respectively, matching the pattern used by PollNotifications.

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Summary by cubic

Gate WebSocket toast notifications by the user's popup settings so disabled types no longer show. bbs_mention now respects BBSPopup and mail_mention respects MessagePopup; version bumped to 3.2.2 (prerelease) and Update.json notes/time updated.

^{Written for commit c6fd5b9. Summary will update on new commits.}

[cubic-dev-ai]

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