YT-19324: move YT provider to ydb/library/yql

This commit is formed by the following script: https://paste.yandex-team.ru/6f92e4b8-efc5-4d34-948b-15ee2accd7e7/text.
This commit has zero effect on all projects that depend on YQL.

The summary of changes:
- `yql/providers/yt -> ydb/library/yql/providers/yt `- the whole implementation of YT provider is moved into YDB code base for further export as a part of YT YQL plugin shared library;
- `yql/providers/stat/{expr_nodes,uploader} -> ydb/library/yql/providers/stat/{expr_nodes,uploader}` - a small interface without implementation and the description of stat expr nodes;
- `yql/core/extract_predicate/ut -> ydb/library/yql/core/extract_predicate/ut`;
- `yql/core/{ut,ut_common} -> ydb/library/yql/core/{ut,ut_common}`;
- `yql/core` is gone;
- `yql/library/url_preprocessing -> ydb/library/yql/core/url_preprocessing`.

**NB**: all new targets inside `ydb/` are under `IF (NOT CMAKE_EXPORT)` clause which disables them from open-source cmake generation and ya make build. They will be enabled in the subsequent commits.

1 files changed, 72 insertions, 0 deletions

diff --git a/yt/cpp/mapreduce/client/skiff.h b/yt/cpp/mapreduce/client/skiff.h
new file mode 100644
index 00000000000..82d80a4967a
--- /dev/null
+++ b/yt/cpp/mapreduce/client/skiff.h
@@ -0,0 +1,72 @@
+#pragma once
+
+#include <yt/cpp/mapreduce/common/fwd.h>
+
+#include <yt/cpp/mapreduce/interface/fwd.h>
+#include <yt/cpp/mapreduce/interface/common.h>
+
+#include <yt/cpp/mapreduce/skiff/wire_type.h>
+#include <yt/cpp/mapreduce/skiff/skiff_schema.h>
+
+#include <util/generic/vector.h>
+
+namespace NYT::NYson {
+struct IYsonConsumer;
+} // namespace NYT::NYson
+
+namespace NYT {
+
+struct TClientContext;
+enum class ENodeReaderFormat : int;
+
+namespace NDetail {
+
+////////////////////////////////////////////////////////////////////////////////
+
+struct TCreateSkiffSchemaOptions
+{
+    using TSelf = TCreateSkiffSchemaOptions;
+
+    FLUENT_FIELD_DEFAULT(bool, HasKeySwitch, false);
+    FLUENT_FIELD_DEFAULT(bool, HasRangeIndex, false);
+
+    using TRenameColumnsDescriptor = THashMap<TString, TString>;
+    FLUENT_FIELD_OPTION(TRenameColumnsDescriptor, RenameColumns);
+};
+
+////////////////////////////////////////////////////////////////////////////////
+
+NSkiff::TSkiffSchemaPtr CreateSkiffSchema(
+    const TVector<NSkiff::TSkiffSchemaPtr>& tableSchemas,
+    const TCreateSkiffSchemaOptions& options);
+
+NSkiff::TSkiffSchemaPtr GetJobInputSkiffSchema();
+
+NSkiff::EWireType ValueTypeToSkiffType(EValueType valueType);
+
+NSkiff::TSkiffSchemaPtr CreateSkiffSchema(
+    const TTableSchema& schema,
+    const TCreateSkiffSchemaOptions& options = TCreateSkiffSchemaOptions());
+
+NSkiff::TSkiffSchemaPtr CreateSkiffSchema(
+    const TNode& schemaNode,
+    const TCreateSkiffSchemaOptions& options = TCreateSkiffSchemaOptions());
+
+void Serialize(const NSkiff::TSkiffSchemaPtr& schema, NYson::IYsonConsumer* consumer);
+
+void Deserialize(NSkiff::TSkiffSchemaPtr& schema, const TNode& node);
+
+TFormat CreateSkiffFormat(const NSkiff::TSkiffSchemaPtr& schema);
+
+NSkiff::TSkiffSchemaPtr CreateSkiffSchemaIfNecessary(
+    const TClientContext& context,
+    const IClientRetryPolicyPtr& clientRetryPolicy,
+    const TTransactionId& transactionId,
+    ENodeReaderFormat nodeReaderFormat,
+    const TVector<TRichYPath>& tablePaths,
+    const TCreateSkiffSchemaOptions& options = TCreateSkiffSchemaOptions());
+
+////////////////////////////////////////////////////////////////////////////////
+
+} // namespace NDetail
+} // namespace NYT