chore: move janitor functions to janitor.py

[eakmanrq]

Follow up from this discussion: #5486 (comment)

[Copilot]

Pull Request Overview

This PR moves janitor functions from the sqlmesh.core.state_sync.common module to a new dedicated sqlmesh.core.janitor module, following discussions in PR #5486. This refactoring improves code organization by centralizing cleanup functionality.

Key changes:

• Creates a new sqlmesh.core.janitor module containing cleanup_expired_views and delete_expired_snapshots functions
• Moves associated test functions to tests.core.test_janitor
• Updates imports throughout the codebase to reference the new module location

Reviewed Changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
tests/core/test_janitor.py	New test file containing moved janitor function tests
tests/core/state_sync/test_state_sync.py	Removed janitor-related tests and cleaned up unused imports
sqlmesh/core/state_sync/common.py	Removed janitor functions and their dependencies
sqlmesh/core/state_sync/__init__.py	Removed cleanup_expired_views import
sqlmesh/core/janitor.py	New module containing moved janitor functions
sqlmesh/core/context.py	Updated imports to use new janitor module

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[izeigerman]

thank you!