feat(mobile): share to mechanism (#15229)

* setup ios

* chore: succesfully sent media to the app

* share from Android

* wip: navigate to share screen

* wip: UI for displaying upload candidate

* wip: logic

* wip: upload logic

* wip: up up up we got it up

* wip

* wip

* wip

* upload state

* feat: i18n

* fix: release build ios'

* feat: clear file cache

* pr feedback

* using const for checking download status

---------

Co-authored-by: Alex <alex@pop-os.localdomain>

mobile/lib/constants/constants.dart

@@ -1 +1,3 @@
 const int noDbId = -9223372036854775808; // from Isar
+const double downloadCompleted = -1;
+const double downloadFailed = -2;