GREEN phase — adds TenderSavedSearch (userId+tenantId scoped, filters
Json, @@unique([userId,name])), the migration (applied to local dev DB),
and TenderSavedSearchService following the FavoritesService/
TenderTriageService pattern: manual where:{userId} scoping (no
forTenant()/RLS), ownership check before update/remove, P2002 unique
conflicts translated to ConflictException.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
