Screen: Add Assets to a pack sheet (iPhone app)

This sheet opens from the green + on a pack's page (the pack as a whole) or from the green + on one of its cases (items into that case).

How to recognise it

A sheet that fills the screen, titled Add Assets, or Add Items to <Case> when adding into a case, or the name of a folder you have opened.
X at the top left. From 1.0.1 a green + appears at the top right once you have picked something.
Two rows of pills at the top: first the pack's profile (its logo and name) | All Assets (with a small grid icon; shown when that profile has assets of yours), then Items | Cases with a box and suitcase icon (hidden when adding into a case). The sheet opens on Cases.
In the profile view: folder tiles like the Assets page, counting only the items (or cases) you can add; a bubble < <name> just above them inside a folder. In All Assets: an All Categories capsule instead.
A search bar Search items… / Search cases…, then "12 items" with Select All on the right.
Rows: a small thumbnail, the name, a subtitle (brand, or "In <Case>"), and a circle on the right: empty, a green tick (already in the pack) or an amber tick (in the pack but somewhere else).

Row: tap to tick or untick it. An asset already in the pack is listed greyed with a green tick; tapping it picks it to come out.
Amber tick: tapping asks Already in <place> with Move to <target>, Remove from Pack and Cancel.
Ticked case: tapping asks Remove <case>?, with a red Remove Case and N Items button that says how many items go with it.
Select All / Deselect All: ticks everything listed that can be picked in bulk.
Folder tile: opens that folder; tapping the profile pill while it's selected returns to its top level. Folders holding nothing you can add are hidden. "No items outside folders." means the top level has none filed loose.
Green + (top right): adds everything picked and closes, with one message such as "Added 3 items to <pack>" (or "<pack> updated" when something was moved or taken out).
X: closes straight away if nothing is picked; otherwise asks Close without adding? with Add Them, Don't Add and Cancel (or Close without saving? with Save / Don't Save when removals are involved). Swiping the sheet down is blocked while something is picked.