docs(adr): shared spaces, their screens in step 4

ADR 0044, D29 to D32: Share opens one sheet, people first, then the
community; a Viewer's studyset screen is read-only; a shared studyset
is marked with people; safety codes are compared from a member's row,
members matched to their keys by handle.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Signed-off-by: Tizian 「ティツィアーン」 <raisondetredev@pm.me>

apps/learn/halkyon_learn_flutter/lib/src/feature/sharing/data/shared_space_gateway.dart

@@ -1,27 +0,0 @@
-import 'package:halkyon_base_client/halkyon_base_client.dart' as base;
-
-/// The shared spaces the instance keeps (halkyon_base's `sharedSpace`
-/// endpoint, Halkyon's ADR 0044, D1).
-abstract interface class SharedSpaceGateway() {
-  /// Makes a shared space holding a studyset, with the person its Owner;
-  /// returns its id, the sync engine's space.
-  Future<String> create();
-
-  /// Deletes [space] with everything in it; its Owner's.
-  Future<void> delete(String space);
-}
-
-/// [SharedSpaceGateway] on halkyon_base's `sharedSpace` endpoint.
-class ServerpodSharedSpaceGateway(final base.Caller _base)
-    implements SharedSpaceGateway {
-  /// What a Learn space holds, in the module's words for it.
-  static const kind = 'studyset';
-
-  @override
-  Future<String> create() async =>
-      (await _base.sharedSpace.create(kind)).id.uuid;
-
-  @override
-  Future<void> delete(String space) =>
-      _base.sharedSpace.delete(base.UuidValue.withValidation(space));
-}

docs/adr/0044-shared-spaces-and-collaboration.md

@@ -4,7 +4,8 @@
   their choices over the agent's recommendations (all ticked at first; agents editing
   directly), D1 to D7 the agent's recommendations, which they chose; D11 to D13 the
   agent's recommendations, which they chose on 11 Nov 2026, D14 too, and D15 to D26;
-  D27 their choice; D28 the agent's, to be confirmed.
+  D27 their choice; D28 the agent's, to be confirmed; D29 to D32 the agent's
+  recommendations, which they chose.
   Steps 1 to 3 built; the rest below.
 - **Builds on:** ADR 0005 (publishing, reports and suggestions), ADR 0014 (the module),
   ADR 0016 (one account across an instance), ADR 0017 (key pairs), ADR 0019 (private
@@ -161,6 +162,24 @@ member reads everything in the space.
   studyset is the same one moved. The old tree is deleted for good once the copy is
   whole; a copy failing or aborted deletes what it wrote and the space it made.
 
+- **D29.** **Share opens one sheet** (decided 11 Nov 2026, the agent's recommendation):
+  People first (the members with their roles, *Invite by @handle*, or *Share with
+  people…* for a studyset not shared yet), then the community part as before (privacy,
+  publishing), as Vaia's Share does.
+- **D30.** **A Viewer's studyset screen is read-only in step 4** (decided 11 Nov 2026,
+  the agent's recommendation): it says *You can view and study this* and hides adding,
+  editing, moving and deleting; a write that slips through elsewhere, which the engine
+  refuses, says so rather than failing silently. Each editor is checked one by one
+  later.
+- **D31.** **A shared studyset is marked with people** (decided 11 Nov 2026, the agent's
+  recommendation): Lucide's *users* in place of the lock, as it is always sealed (D21),
+  labelled *Shared · private*.
+- **D32.** **Safety codes are compared from a member's row** (decided 11 Nov 2026, the
+  agent's recommendation): their screen shows the code in twelve groups of five and
+  *Mark as compared*; a member whose keys changed is flagged on their row, and their
+  new keys are trusted on that screen, after comparing. Members are matched to their
+  keys by handle, as the member list names nobody by account ID.
+
 ## Steps
 
 1. **Share with the community's confirmation** (D8, D9), needing nothing else here.