feat: Добавлен интерфейс Cache

go.mod

go.sum

pkg/account/client.go

pkg/cache/cache.go

pkg/cache/memory_cache.go

pkg/cache/memory_cache_test.go

pkg/clients/middleware/caching_middleware.go

pkg/clients/middleware/caching_middleware_test.go

pkg/collaborators/middleware/caching_middleware.go

pkg/collaborators/middleware/caching_middleware_test.go

pkg/collections/middleware/caching_middleware.go

pkg/collections/middleware/caching_middleware_test.go

pkg/content/client.go

pkg/delivery/client/client.go

pkg/environments/middleware/caching_middleware.go

pkg/environments/middleware/caching_middleware_test.go

pkg/invitations/middleware/caching_middleware.go

pkg/invitations/middleware/caching_middleware_test.go

pkg/items/middleware/caching_middleware.go

pkg/items/middleware/caching_middleware_test.go