EnvironmentLoader.Load() previously returned (empty Catalog, nil) on all
failure paths, making it impossible for callers to distinguish "no services
available" from "discovery failed due to auth/network issues".
Changes:
- Add CatalogDegraded error type with three reasons: unauthenticated,
market_unreachable, runtime_all_failed
- Add auth pre-check: return DegradedUnauthenticated immediately when no
token is available, avoiding doomed MCP connections
- Schema command now handles CatalogDegraded gracefully: outputs hint to
stderr and includes degraded/reason/hint fields in JSON output
- Runner preserves graceful degradation by ignoring CatalogDegraded errors
- Skip empty-products cache to prevent stale cache from masking auth errors
- Edition-aware hint text (open-source vs embedded/wukong)
Made-with: Cursor
wxianfeng
713fdf6188