Type validation for table ranges/pivot keys in operations

Recently, we have encountered a few situations in which users used integers of the wrong type when specifying table ranges and pivot keys in operations. This led to unexpected results, since in YT integers of different types are compared according to their order in the C++ value type enum (e.g. any int64 value is smaller than any uint64 value).

Let's think about validating the specified values against the table/chunk schema, or maybe even cast them automatically, if possible.