Share sheet: ask to unlock on every gated action, like the app

The sheet remembered one unlock for its whole lifetime, so later account picks
and hidden toggles skipped Face ID. Each switch / each turning-on of hidden
folders now prompts again; one action needing both is a single prompt.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

.claude/context/server.md

@@ -935,7 +935,15 @@ Reminders/Notes - the destination is picked *inside* the sheet:
      hidden, with a note. Switching `only` <-> `all`, or back to `hide`, never
      asks.
    - **Account switching**: choosing any account other than the app's
-     active one asks for the same unlock when "lock account switching" is on. One successful unlock covers the rest of that sheet.
+     active one asks for the same unlock when "lock account switching" is on.
+     **Every gated action prompts every time**, exactly like the app - no
+     unlock is remembered for the sheet (an earlier version cached one, so
+     later account picks / hidden toggles skipped Face ID). The only
+     merging is within one action: picking another account whose own filter
+     already shows hidden folders is a single prompt covering both
+     (`SharedAccounts.unlockNeeds` / `SelectionUnlock`, unit-tested).
+     Declining the account unlock cancels the pick; declining only the
+     hidden unlock shows the account with hidden folders hidden.
    - Opening the sheet itself is not gated - only these two actions are
      (as in the app, where login lock guards launch and these are separate
      locks).