新增兩個測試:cloud provider 被跳過 + 全失敗回傳 local_providers_unavailable。 實作邏輯已存在於 AIRouterExecutor.execute()(2026-04-04 ogt Phase 25 P0)。 Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>