feat(web): 对齐桌面标准工作台布局

[Xavier-Trump]

Summary

• Align Web with the Desktop Command Center surface model: compact toolbar, left navigation, routed main content, and right status/source panel.
• Add shared surface metadata registry for Desktop/Web status boundaries and route/section lookup.
• Tighten Desktop Settings status labels so loading/error/interface gaps are not shown as real snapshots.

Boundaries

• Frontend-only: app/shared, app/web, app/desktop.
• No Go/API/backend changes.
• No new third-party libraries.
• No TokenDance OIDC callback implementation.
• Demo/catalog fallback and interface gaps remain visibly labeled as fallback/gap states.

Validation

• git diff --check
• corepack.cmd pnpm --dir app/shared test
• corepack.cmd pnpm --dir app/desktop test
• corepack.cmd pnpm --dir app/desktop typecheck
• corepack.cmd pnpm --dir app/desktop build
• corepack.cmd pnpm --dir app/web test
• corepack.cmd pnpm --dir app/web typecheck
• corepack.cmd pnpm --dir app/web build
• rg ^<<<<<<<|^>>>>>>> app api docs