Refactor session lifecycle

[vgvoleg]

Pull request type

Please check the type of change your PR introduces:

• Bugfix
• Feature
• Code style update (formatting, renaming)
• Refactoring (no functional changes, no api changes)
• Build related changes
• Documentation content changes
• Other (please describe):

What is the current behavior?

Issue Number: N/A

What is the new behavior?

Other information

[Copilot]

Pull request overview

This pull request refactors the session lifecycle management in the YDB Query Service implementation, removing the complex state machine pattern in favor of simpler flag-based state tracking.

Changes:

• Removed QuerySessionState, QuerySessionStateEnum, and IQuerySessionState interface, moving session state directly into BaseQuerySession as simple attributes
• Added session invalidation on DeadlineExceed errors through a new error callback mechanism in response iterators
• Changed DeadlineExceed exception to inherit from Error instead of ConnectionError

Reviewed changes

Copilot reviewed 13 out of 13 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
ydb/query/session.py	Removed state machine classes, added _invalidate() method and error handling, simplified session lifecycle
ydb/query/transaction.py	Updated to use session directly instead of session_state, added TYPE_CHECKING imports, updated error handlers
ydb/query/base.py	Removed IQuerySessionState interface, added on_error callback to response iterators, updated handler signatures
ydb/query/pool.py	Updated to use session.session_id and session.is_active instead of state object
ydb/issues.py	Changed DeadlineExceed to inherit from Error instead of ConnectionError
ydb/aio/query/session.py	Mirror of sync changes for async implementation
ydb/aio/query/transaction.py	Mirror of sync changes for async implementation
ydb/aio/query/base.py	Added async version of error handling in response iterator
ydb/aio/query/pool.py	Updated to use session properties instead of state object
tests/query/test_query_session.py	Updated tests to reflect new state management and behavior changes
tests/query/test_query_session_pool.py	Updated tests to use session properties
tests/aio/query/test_query_session.py	Updated async tests to reflect new state management
tests/aio/query/test_query_session_pool.py	Updated async pool tests to use session properties

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[Copilot]

Changing DeadlineExceed from inheriting ConnectionError to Error is a breaking change. Code that catches ConnectionError specifically will no longer catch DeadlineExceed exceptions. Consider whether this change aligns with the PR's stated type as "Bugfix" - breaking changes typically warrant a feature or refactoring PR. If this is intentional, ensure all callers that catch ConnectionError are updated to handle DeadlineExceed appropriately, or document this as a breaking change.

Suggested change

	class DeadlineExceed(Error):
	class DeadlineExceed(ConnectionError):

[vgvoleg]

ну дружище, это бага была. люди таймауты ставили и уходили в цикл ретраев.

[github-actions]

🌋 SLO Test Results

Status: 🔴 2 workloads tested • 2 workloads failed

	Workload	Metrics	Regressions	Improvements	Links
🔴	ydb-python-sync-table	8	2	0	Report • Check
🔴	ydb-python-sync-query	8	2	0	Report • Check

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