Hide Collection and Species sharing entry points and guard modal navigation/restoration during beta. Non-beta sharing and CSV import remain available.

Mobile PR #703 targets staging and is not merged. Observed focused RED/GREEN, lint/typecheck passed and 2498 Jest tests passed with 11 pre-existing skips. Maestro assertions are prepared but not executed because the executable is unavailable. Native image/layout validation remains pending; no build or deployment is claimed. Notion was updated with the PR, date, evidence and limitations, preserving historical remarks.