feat(plugin-kanban,types): honour columns[].collapsed on the registered board (objectui#9628)

.changeset/8801-object-kanban-allow-collapse-retired.md

@@ -50,13 +50,14 @@ near miss of the same spelling parses GREEN rather than red — this arm is not
 strict, which is precisely why the tombstone rather than a deletion is what does
 the refusing here.
 
-**What replaces it: nothing you author.** Lane collapse is
-`KanbanColumn.collapsed`'s — a per-lane member — not a board-level authored
-toggle. On the board this arm actually renders it is the VIEWER's rather than
-the author's: `KanbanImpl` collapses a swimlane when its header button is
-clicked and persists that set per `swimlaneField`. The implementation that does
-honour a lane's own `collapsed`, `KanbanEnhanced`, is referenced by no
-registration since the `kanban-enhanced` node key retired (objectui#8257).
+**What replaces it: the per-LANE member, not a board-level toggle.** Lane
+collapse is `KanbanColumn.collapsed`'s — written on the lane you want collapsed,
+inside `columns` — and the board this arm renders honours it (objectui#9628, in
+this same release): the lane starts collapsed and the viewer can open it again.
+A board-level "may lanes collapse at all" switch is what has no replacement.
+SWIMLANE collapse remains the viewer's alone: `KanbanImpl` collapses a swimlane
+row when its header button is clicked and persists that set per `swimlaneField`,
+and no authored key reaches it.
 
 **Migration, in this repository: no authored document changed.** Over every
 tracked file, the only occurrences of the name were the two declarations retired

.changeset/9628-kanban-column-collapsed-honoured.md

@@ -0,0 +1,41 @@
+---
+'@object-ui/plugin-kanban': minor
+'@object-ui/types': minor
+---
+
+Honour `columns[].collapsed` on the registered kanban board (objectui#9628).
+
+The key was declared on **both** published faces of the `object-kanban` arm — the lane
+element of `ObjectKanbanSchema` (`objectql.ts` and its Zod mirror) and the runtime lane
+`KanbanColumn` (`complex.ts` and its mirror) — and read by `KanbanEnhanced` alone, a
+module no production source imports. An authored `{ "id": "todo", "title": "To Do",
+"collapsed": true }` therefore parsed green on both faces and reached a board that did
+nothing with it: `KanbanImpl`'s only collapse is the SWIMLANE row's, held in viewer
+state under `objectui:kanban-collapsed:<swimlaneField>` and never keyed to a lane's
+declared value. That is the ADR-0049 declared-but-unhonoured shape.
+
+**The repair is at the reader, not at the declaration.** Retiring the key would narrow a
+published accept set, and it would also strand objectui#8801's retirement tombstone,
+which names `KanbanColumn.collapsed` as where lane collapse lives. Honouring it moves no
+accept set in either direction: both faces already declare the member, and
+`@objectstack/spec` declares the lane element as `z.unknown()`, so the protocol neither
+names the key nor refuses it. Nothing that parsed before parses differently now.
+
+**What an authored `collapsed: true` does.** The lane renders narrowed to a title spine
+with its cards withheld, on **both** of the board's layouts — the flat lane and the
+column cells of each swimlane row — and its heading becomes a disclosure the viewer can
+open. That is the meaning `KanbanEnhanced` already gave the key, so the platform states
+one behaviour for it rather than two.
+
+The authored value is the lane's **initial** state. A viewer's own toggle wins after
+that and survives the data refreshes that rebuild the lane objects: the board holds the
+viewer's overrides and resolves them against the current prop, rather than copying the
+authored flags into state where every refetch would re-collapse a lane the viewer had
+opened. A lane whose cards could never be reached again — and whose drop target was
+blind — would have been a worse board than the one that ignored the key.
+
+**No change to a board that does not author the key.** The disclosure appears only on a
+lane that declared `collapsed: true`, so an omitted key and an authored `collapsed:
+false` are indistinguishable, and a board authoring neither renders the DOM it rendered
+before. The published `describe` text and docblocks on both faces, the plugin README and
+the plugin docs page stop pointing authors at the unregistered board.

content/docs/plugins/plugin-kanban.mdx

@@ -143,7 +143,7 @@ interface KanbanLane {
   cards?: KanbanCard[]        // a STATIC board's lane only
   limit?: number              // Max cards allowed (WIP limit)
   className?: string
-  collapsed?: boolean         // honoured by the enhanced board
+  collapsed?: boolean         // lane starts collapsed; the viewer can reopen it
 }
 
 interface KanbanCard {
@@ -177,7 +177,7 @@ An undeclared lane key is accepted and dropped, not refused.
 | `cards` | KanbanCard[] | Cards this lane carries — **optional**, and a static board's option; an object-bound board's cards arrive from the record source |
 | `limit` | number | Max cards allowed (WIP limit). Never reaches the query — the fetch window is the board's `limit` |
 | `className` | string | Additional Tailwind CSS classes |
-| `collapsed` | boolean | Whether the lane renders collapsed (honoured by the enhanced board) |
+| `collapsed` | boolean | Whether the lane renders collapsed — narrowed to a title spine with its cards withheld, and its heading a disclosure the viewer can open. The authored value is the lane's INITIAL state: once a viewer toggles the lane, their choice holds for the session, including across data refreshes |
 
 ### Card Properties
 

packages/plugin-kanban/README.md

@@ -165,9 +165,9 @@ interface KanbanColumn {
   cards: KanbanCard[];
   limit?: number;                     // WIP limit — the count at which the lane warns
   className?: string;
-  collapsed?: boolean;                // Lane renders collapsed (read by the KanbanEnhanced
-                                      // source module, which objectui#8257 left
-                                      // with no registry key — see CHANGELOG)
+  collapsed?: boolean;                // Lane starts collapsed — narrowed to a title
+                                      // spine, cards withheld, heading a disclosure
+                                      // the viewer can reopen (objectui#9628)
   color?: never;                      // RETIRED — refused by name; style a lane through className
 }