feat(identity): Org Chart tree view for sys_business_unit (#2189)

sys_business_unit is already a self-referencing hierarchy
(parent_business_unit_id, ADR-0057 D2) with BFS graph traversal, but Setup only
exposed flat grids. Adds an `org_chart` list view (type: 'tree') that renders the
hierarchy as an indented, expand/collapse tree-grid, listed first so it's the
default tab. No schema change — only surfaces the existing parent pointer. The
active/inactive/by_kind/all grids stay for search, filter, and bulk edit.

Uses the 'tree' view type added in #2184; renderer is objectui plugin-tree.

Co-authored-by: Jack Zhuang <277994282+os-zhuang@users.noreply.github.com>
Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>

Author: 3 people

.changeset/bu-org-chart-tree-view.md

@@ -0,0 +1,13 @@
+---
+"@objectstack/platform-objects": minor
+---
+
+feat(identity): add an Org Chart tree view to `sys_business_unit`
+
+`sys_business_unit` is already a self-referencing hierarchy
+(`parent_business_unit_id`, ADR-0057 D2) but Setup only exposed flat grids. Adds
+an `org_chart` list view (`type: 'tree'`) that renders the hierarchy as an
+indented, expand/collapse tree-grid, listed first so it's the default tab. No
+schema change — the parent pointer and graph traversal already existed; this only
+surfaces them. The `active` / `inactive` / `by_kind` / `all` grids stay for
+search, filter, and bulk edit.

packages/platform-objects/src/identity/sys-business-unit.object.ts

@@ -33,6 +33,24 @@ export const SysBusinessUnit = ObjectSchema.create({
   compactLayout: ['name', 'kind', 'parent_business_unit_id', 'manager_user_id'],
 
   listViews: {
+    // Org chart — the hierarchy view. Surfaces the self-referencing
+    // `parent_business_unit_id` tree (ADR-0057 D2) as an indented, expand/
+    // collapse tree-grid. Listed first so it's the default tab; the grids
+    // below stay for search / filter / bulk edit.
+    org_chart: {
+      type: 'tree',
+      name: 'org_chart',
+      label: 'Org Chart',
+      data: { provider: 'object', object: 'sys_business_unit' },
+      columns: ['name', 'kind', 'manager_user_id', 'active'],
+      tree: {
+        parentField: 'parent_business_unit_id',
+        labelField: 'name',
+        fields: ['kind', 'manager_user_id', 'active'],
+        defaultExpandedDepth: 1,
+      },
+      sort: [{ field: 'name', order: 'asc' }],
+    },
     active: {
       type: 'grid',
       name: 'active',