fix(spec): mirror highlightFields back onto compactLayout during transition

Browser dogfood of the rename found a live gap: metadata authored with the
canonical highlightFields key parsed to output WITHOUT compactLayout, so
current renderers that still read the old key (ObjectGrid default columns,
card compact views, vendored console) silently lost their curated field
list. The alias now mirrors both directions (canonical wins when both are
present); the back-fill is removed together with the deprecated key.

Verified end-to-end in a running app (app-todo, HMR console against the
worktree server): default list columns, mobile card fields, detail
highlight strip, stageField stepper, and field-group form sections all
render from the renamed keys.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

Author: os-zhuang

packages/spec/src/data/object.test.ts

@@ -902,6 +902,9 @@ describe('ObjectSchema semantic roles (ADR-0085)', () => {
       name: 'account', fields: {}, highlightFields: ['name', 'industry'],
     });
     expect(direct.highlightFields).toEqual(['name', 'industry']);
+    // Transition mirror: old-key readers (current objectui) still see
+    // compactLayout for metadata authored with the canonical name.
+    expect(direct.compactLayout).toEqual(['name', 'industry']);
 
     const aliased = ObjectSchema.parse({
       name: 'account', fields: {}, compactLayout: ['name', 'industry'],

packages/spec/src/data/object.zod.ts

@@ -905,7 +905,12 @@ function normalizeNameFieldAlias(input: unknown): unknown {
  * (same pattern as `normalizeNameFieldAlias`; deprecated keys are PRESERVED
  * on output for cross-repo back-compat):
  *
- * - `compactLayout` → `highlightFields` when the canonical key is absent.
+ * - `compactLayout` ⇄ `highlightFields`: whichever key is present is mirrored
+ *   onto the other (canonical wins when both exist). The BACK-fill
+ *   (highlightFields → compactLayout) is a transition mirror so renderers
+ *   that still read the old key (current objectui / vendored console) keep
+ *   their default columns for metadata authored with the new name; it is
+ *   removed together with the alias.
  * - `fieldGroups[].collapse` derived from the deprecated flags when absent:
  *   the UI-dialect `collapsible`/`collapsed` pair wins over the old
  *   `defaultExpanded` (it is what designer-authored metadata actually
@@ -920,6 +925,9 @@ function normalizeSemanticRoleAliases(input: unknown): unknown {
 
   if (obj.highlightFields == null && Array.isArray(obj.compactLayout)) {
     out = { ...out, highlightFields: obj.compactLayout };
+  } else if (obj.compactLayout == null && Array.isArray(obj.highlightFields)) {
+    // Transition mirror for old-key readers (see doc comment above).
+    out = { ...out, compactLayout: obj.highlightFields };
   }
 
   if (Array.isArray(obj.fieldGroups)) {