chore(backend)(deps): update sqlalchemy[asyncio] requirement from >=2.0.25 to >=2.0.51 in /backend

[dependabot]

Updates the requirements on sqlalchemy[asyncio] to permit the latest version.

Release notes

Sourced from sqlalchemy[asyncio]'s releases.

2.0.51

Released: June 15, 2026

orm

• [orm] [bug] Fixed issue where _orm.subqueryload() combined with PropComparator.of_type() and PropComparator.and_() would silently drop the additional filter criteria, causing all related objects to be loaded instead of only those matching the filter. The LoaderCriteriaOption was being constructed against the base entity rather than the effective entity indicated by PropComparator.of_type(). Pull request courtesy Arya Rizky.

  References: #13207

• [orm] [bug] Fixed bug where a failure during tpc_prepare() within _orm.Session.commit() for a two-phase session would raise IllegalStateChangeError instead of the original database exception. The internal _prepare_impl() method's error handler was unable to invoke _orm.SessionTransaction.rollback() due to a state-change guard, preventing proper cleanup and masking the underlying error.

  References: #13356

engine

• [engine] [bug] Fixed issue where Result.freeze() would lose track of ambiguous column names present in the original CursorResult, causing key-based access on the thawed result to silently return a value instead of raising InvalidRequestError. The SimpleResultMetaData now accepts and propagates ambiguous key information so that frozen, thawed, and pickled results raise consistently for duplicate column names. Pull request courtesy Saurabh Kohli.

  References: #9427

sql

• [sql] [bug] Fixed issue where _sql.StatementLambdaElement would proxy attribute access through the cached "expected" expression rather than the resolved expression, causing stale closure-bound parameter values to be used when a lambda statement was extended with non-lambda criteria such as an additional .where() clause. Courtesy cjc0013.

  References: #10827

... (truncated)

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[berntpopp]

Superseded by #452, which consolidates these backend dependency updates into one resolver-consistent change and is green in GitHub Actions.

[dependabot]

OK, I won't notify you again about this release, but will get in touch when a new version is available. If you'd rather skip all updates until the next major or minor version, let me know by commenting @dependabot ignore this major version or @dependabot ignore this minor version. You can also ignore all major, minor, or patch releases for a dependency by adding an ignore condition with the desired update_types to your config file.

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