feat(sharing): unified document + list sharing screen (web parity)

[Adron]

Stacked on #30 (base = feat/shared-list-inbound-viewer). Merge #30 first, then retarget this to main.

Summary

Brings iOS document (and list) sharing to parity with the web's single "Access & Permissions" screen. The capabilities existed but were scattered across separate sheets (Share / Invite by email / Collaborators / Watchers) with the public toggle buried in Edit — which is why it "didn't appear to show up." This replaces them with one SharingView, generic over documents (collaborators) and lists (watchers).

What's included

• Access & Permissions: search + "Role for new users" + an "Email this person" toggle (the notify flag; default on) + a members list with role menu, per-user Get link, and Remove.
• Invite by email (pending + revoke) and Share links (roles labeled Viewer/Editor/Admin; expiry presets Never / 7d / 30d).
• Make public toggle with a copyable canonical public link.
• Foundations: WatcherRole.accessLabel/linkLabel, ShareExpiryPreset, ILWebURL.publicResource/resource, and notify added to the list addWatcher/setWatcherRole (documents already had it).
• DocumentsView/ListsView now open the single SharingView.

Testing

• Build: succeeded.
• Full unit suite (excl. live E2E): 819 passing, 0 failures (+10 new: role labels, expiry presets, watcher notify body, ILWebURL builders).

Caveats

• The live screen (search/add/toggle/public-link) is owner-only behind login, not runtime-verified here — worth an on-device or qa-screenshotter pass.
• The old sharing views (DocumentCollaboratorsView, WatchersListView, ShareLinksSheet, ShareInvitesSheet) are now orphaned; removal left as a follow-up.

🤖 Generated with Claude Code

https://claude.ai/code/session_01V16mvNBWyYLncSQL8isDNF