YQL-21207: Add langver and settings hash to cache

2026-06-25T12:26:10Z

#### `YQL-21207`: Enhance cache key with langver and settings hash ✎ - Replaced serialized program string with a composite key consisting of language version, runtime settings hash, and serialized program to uniquely identify computation patterns. - Updated cache lookup, insertion, and notification mechanisms to use the new composite key for improved cache accuracy and consistency. - Modified pattern compilation and subscription logic to utilize the enhanced key for better cache management and pattern reuse. - Added unit tests to verify that the new key correctly distinguishes between different combinations of language version, settings, and program content. Autodescription by Yandex Code Assistant commit_hash:db8a7b700579271bf301f1a2d40f662d77da424f

ydb/yql/essentials/minikql/computation/mkql_computation_pattern_cache_program_key.h, branch main

YQL-21207: Add langver and settings hash to cache