[SDUI][P1] Schema-driven app navigation (NavigationDesigner runtime wiring)

[xuyushun441-sys]

Context

App navigation is currently hardcoded routes, not a schema-driven nav tree. NavigationDesigner exists but isn't wired to runtime.

Goal

Drive the app navigation (groups, items, icons, ordering, visibility) from an App/navigation schema, editable at runtime.

Scope

• Render the nav tree from the App metadata schema (already partly defined in spec ui/app.zod).
• Wire NavigationDesigner edits → draft/publish seam.
• Support reorder / show-hide / grouping without code changes.

Acceptance

• Sidebar nav renders from schema
• Visual reorder/edit persists via draft/publish
• No hardcoded per-object route assumptions remain in the nav