MYCDIC v1.9.30.7 - Council Announcement Button Reliability Fix

- The Council Announcements bell is now always created by the shared site shell, even when there are zero active announcements.
- The control still remains hidden at the top of the page and appears after the user scrolls more than 300px, matching the back-to-top behavior.
- Desktop geometry is fixed to 50x50 at right:24px with a 12px vertical gap above the back-to-top control.
- Mobile keeps the accepted 44x44 placement.
- With zero announcements, the bell opens a clear empty state instead of disappearing.
- If the public-experience API is temporarily unavailable, the bell still exists and opens the empty state.
- Unread badge remains hidden when there is nothing new and appears only for unread active announcements.
- Dashboard navigation now exposes a direct Council Announcements entry that jumps to the announcement manager.
- Cache versions moved to v1.9.30.7 so browsers do not keep the older shell behavior.
