feat: Refactor work item management and documentation for clarity and structure

.opencode/commands/promote-project-context.md

@@ -12,6 +12,7 @@ Read:
 @ai/context/systems/index.md
 @ai/context/workstreams/index.md
 @ai/context/process/index.md
+@ai/work-items/index.md
 @ai/state/current.md
 @ai/state/work-items.md
 @knowledge/workspace-model.md
@@ -41,6 +42,7 @@ Instructions:
 - Update the smallest correct set of files among:
   - `ai/logs/$(date +%F).md`
   - `ai/state/current.md`
+  - `ai/work-items/*.md`
   - `ai/state/work-items.md`
   - `ai/context/project.md`
   - `ai/context/systems/*.md`