feat docs: changelog-tool

[Malevrovich]

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[Malevrovich]

Пример генерации для 3.1:

* Breaking Change

  * core

    * Changed X-Request-Deadline header format from ISO timestamp to Unix epoch microseconds. Migration: Update clients to send deadlines as uint64_t microseconds since Unix epoch instead of ISO strings. <!-- ceb559ac -->

  * engine

    * Removed obscure overloads of engine::Async and utils::Async variants. Migration: Use utils::TaskBuilder for complex task settings instead of the removed overloads. <!-- e73a3ebc -->

  * grpc/tests

    * Changed ugrpc::tests::Service constructor signature. Migration: Pass server config, middlewares, and client settings through ugrpc::tests::ServiceConfigs instead of direct constructor parameters. <!-- 02522b55 -->

  * userver

    * Replaced utils::void_t with C++20 requires constraints in PostgreSQL type traits. Migration: Update custom type trait specializations to use requires clauses instead of std::enable_if conditions. <!-- 0b04131a -->
    * Raised minimum GCC version from 11.1 to 11.2 to enable C++20 heterogeneous lookup in hash containers. Migration: Update your GCC compiler to version 11.2 or newer. <!-- 288c7e7c -->

  * ydb

    * Changed YDB topic API: GetNativeTopicReadSession/GetNativeTopicWriteSession now return references instead of shared_ptr. Migration: Remove dereference operator (*) or -> when calling methods on the returned native session objects. <!-- a0d306f2 -->

  * Changed graceful shutdown procedure to two stages. Migration: replace `graceful_shutdown_interval` with `graceful_shutdown_continue_accepting_requests_interval` and `graceful_shutdown_pending_requests_completion_interval` in your config. The old parameter is deprecated and will be removed in the future. <!-- 56b3b2da -->

* Feature

  * all

    * Enabled three-way comparison operator (<=>) support unconditionally across the codebase <!-- a07ffe8c -->

  * chaotic

    * Improved support for allOf schemas with additionalProperties in chaotic serialization <!-- 0dd5cc3b -->
    * Added support for JSON Schema 'const' keyword in chaotic code generation <!-- d795f94d -->
    * Added support for 'any' type in chaotic schema generator, allowing arbitrary JSON values without type constraints. <!-- f59bbeed -->
    * Added JSON stream writer generation for chaotic schemas, improving serialization performance <!-- 20b36c01 -->
    * Added support for uniqueItems validation in chaotic array schemas for integer, string, and boolean types <!-- 86a10abb -->
    * Chaotic OpenAPI generator: added automatic config.yaml generation, improved handler generation, and enhanced documentation <!-- f3115e35 -->
    * Added comprehensive OpenAPI handler generation support with multiple content types, request body parsing, logging customization, and URL masking for sensitive parameters <!-- e616760e -->
    * Added OpenAPI handler code generation support for server-side HTTP handlers <!-- 525eba65 -->
    * chaotic: Added support for emoji characters in enum and field names by escaping them as Unicode code points <!-- ca356ebd --> Many thanks to Halfdarkangel for the PR!

  * engine

    * Added engine::AwaitableToken API and engine::Awaitable concept for integration with WaitAny/WaitAllChecked. Replaced TryGetContextAccessor() hooks with GetAwaitableToken() for creating custom awaitables. <!-- 4079a9a8 -->
    * Added utils::AsyncHideSpan for creating tasks with hidden spans that preserve log linking <!-- eefe9858 -->

  * grpc

    * feat grpc: Added validation for proto2 required fields before sending responses, providing better error messages <!-- 4c434fa1 -->
    * Added deadline propagation handling for gRPC client streaming calls <!-- 93b53d86 -->
    * Added absolute timepoint propagation support for gRPC client-side deadline propagation <!-- 54614329 -->
    * gRPC server now processes calls in subtasks, enabling Congestion Control to properly handle service overload <!-- de70eb2a -->
    * gRPC: Added graceful shutdown headers to trailing metadata for streaming calls when shutdown starts after initial metadata has been sent <!-- 5a9e7074 -->

  * kafka

    * Kafka consumer now automatically recreates itself after fatal librdkafka errors (configurable via 'restart_after_failure_delay') <!-- 894551a0 -->

  * logging

    * tracing::Span::SetLocalLogLevel now overrides the global log level in both directions - can raise the threshold (suppress logs) or lower it (enable debug logs even if the global level is higher) <!-- 2ffc7724 -->

  * mongo

    * Added OperationError getter to mongo::WriteResult for better error handling with SuppressServerExceptions option <!-- 8453f5e7 -->

  * odbc

    * Added comprehensive ODBC driver support including connection pooling, transactions, deadlines, and component configuration <!-- 64d5b74f --> Many thanks to Andrey Balabekyan for the PR!

  * postgresql

    * Added connecting_interval_ms option to PostgreSQL connection pool for throttling connection attempts <!-- ad37210b -->

  * redis

    * Added support for Redis hash field expiration commands (HEXPIRE, HPEXPIRE, HEXPIREAT, HPEXPIREAT, HEXPIRETIME, HPEXPIRETIME, HTTL, HPTTL, HPERSIST, HGETEX, HSETEX) <!-- 332799e3 -->
    * Added `SetAndGetPrevious` method to Redis client and transaction interfaces for atomic set-with-TTL operations that return the previous value <!-- c736fe02 -->
    * Added support for suppressing per-channel Redis Pub/Sub metrics to reduce metrics volume when using many channels <!-- 018efdbb -->
    * Added Redis JSON module support with json.set, json.get, json.mset, and json.mget commands <!-- f4cb5f36 -->
    * feat redis: add support for CLUSTER SHARDS topology update method <!-- 4661929e -->

  * testsuite/grpc

    * grpc.Mockserver now properly manages mock lifecycle with scope-based ownership, enabling nested and overlapping mock scopes for complex testing scenarios <!-- 3a1962b8 -->

  * userver

    * Added YDB database routing via dynamic config for blue-green deployments and live migrations <!-- 144fef36 -->
    * Added OpenTelemetry trace sampling support for gRPC servers. When enabled, gRPC requests now respect the sampling flag from incoming traceparent headers. <!-- f84a9a53 -->
    * Added support for OpenTelemetry trace sampling flags. When 'otel-trace-sampling-enabled' is true, spans will respect the W3C trace-context sampled flag (unsampled spans are not written to tracing systems). Added Span::IsSampled() and Span::SetSampled() methods for manual control. <!-- c580979b -->
    * Added full HTTP/2 over TLS support with ALPN negotiation <!-- 13d761fe --> Many thanks to SSE4 for the PR!
    * Added ScyllaDB driver: asynchronous C++ driver for ScyllaDB and Apache Cassandra with full CQL support, typed operations, and lightweight transactions <!-- b2dc90c2 --> Many thanks to gearonixx for the PR!
    * Added support for parsing all Redis command control configuration fields including account_in_statistics, force_shard_idx, chunk_size, force_retries_to_master_on_nil_reply, and retry_counter <!-- 985239a8 -->
    * Fixed MongoDB transactions to properly use dedicated client sessions. Transaction collections now prohibit cursor operations (Find, Aggregate) that could lead to undefined behavior. <!-- df8cb397 -->

  * userver/postgresql

    * Added PostgreSQL support for std::span types as array formatters <!-- 6bbd4ac3 -->
    * Added chaos testing infrastructure for PostgreSQL to detect message handling issues under network irregularities <!-- 9fbbaade -->

  * userver/ydb

    * Added deadline support for YDB topic producer flush operations <!-- 3e643f33 -->
    * Added TopicProducer wrapper for YDB topic message publishing <!-- 1fb7f5cf -->
    * Added TCP and gRPC keepalive configuration options to YDB driver <!-- ec9e2642 -->

  * utils

    * Migrated utils::span to use C++20 std::span implementation with enhanced features <!-- 8d7fb78c -->

  * ydb

    * Added support for YDB tuple type serialization with std::tuple support <!-- 5039c851 -->
    * Added TopicWriteSession support to YDB client for coroutine-friendly topic writing <!-- 5c60bc53 --> Many thanks to Vasily Sviridov for the PR!

  * Added support for Redis ACL authentication (Redis 6+) with username/password credentials <!-- 24c93522 -->
  * Added support for multiple channels in Redis subscribe commands (Subscribe, Psubscribe, Ssubscribe) <!-- e964f1f0 -->
  * crypto: Added PublicKey::LoadFromPrivateKey method to derive public keys from private keys <!-- 69dbd2de --> Many thanks to Georgij Tsarin for the PR!

* Optimization

  * grpc

    * Optimized gRPC server to parse and serialize messages from raw grpc::ByteBuffer, allowing congestion control to reject calls before parsing unary request payloads. <!-- 88ba163b -->

  * universal

    * Optimized various utility functions to use string views instead of strings, reducing unnecessary string copies. <!-- 02e1e566 -->

* Refactor

  * engine

    * refactor: Renamed engine::AsyncNoSpan to engine::AsyncNoTracing to clarify its purpose and prevent misuse <!-- 5b9e81b2 -->

  * userver

    * Improved resource lifetime management for metrics subscriptions using RegisterWriterScope to prevent race conditions during component initialization and destruction <!-- 262948c9 -->

* Many thanks to:
  * Alexander Ermakov for feat docs: duplicates removed!
  * Artyom Kolpakov for:
    * fix universal: use std::addressof in FindTransparentOrNullptr
    * docs universal: adjust RateCounter description
    * fix universal: use std::addressof in utils::Required
    * fix postgresql: fix confusion with std::forward
    * fix universal: use std::addressof in implementation of OptionalRef
    * docs universal: remove incorrect deprecated tag
    * fix universal: use std::addressof in FindOrNullptr
    * fix universal: support generators for GenerateFixedArray that return const &
    * fix utils: make comparison operators of CachedHash consistent
  * Fedor Shatokhin for fix chaotic: fixup chrono milliseconds convert!
  * Halfdarkangel for:
    * fix chaotic: respect cmake libdir path variable for bash wrapper
    * fix userver build without USERVER_FEATURE_UBOOST_CORO
  * Konstantin Goncharik for:
    * feat llhttp: upgrade to 9.4.1
    * feat service_template: upgrade get_cpm.cmake to 0.42.1
    * feat mongo: add CMake support for mongo-c-driver 2.x.x
  * Merzlikin-Matvey for fix s3api: fix ListBucketContentsParsed with truncation!
  * SSE4 for:
    * feat build: on debian trixie, system abseil package uses its own string_view
    * feat build: debian trixie doesn't have libgrpc++1, use libgrpc++1.51t64 instead
  * Vasily Sviridov for feat build: enable clickhouse by default and require clickhouse-cpp >= 2.6.0!
  * netliomax25-code for fix websocket: avoid size_t overflow in frame length check!
  * seriouscoder43 for feat universal: fix issues in crypto error handling!

[apolukhin]

LGTM

[robot-magpie]

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