Check SQLAlchemy update values against mapped fields

[WilliamK112]

Summary:

• Add a focused SQLAlchemy check for sqlalchemy.update(Model)...values(field=...) keyword arguments.
• Validate explicit values() keyword names against Mapped[...] fields on the model, and validate value types against the mapped instance attribute type.
• Cover chained update calls such as .where(...).values(...) with a regression test for support sqlalchemy update values field check #4046.

Closes #4046.

Validation:

• cargo +stable-x86_64-pc-windows-gnu test -p pyrefly --lib test::descriptors (50 passed)
• Real sqlalchemy==2.0.41 temp sample reports the expected credential_id type error, name type error, and missing_field unknown-field error
• cargo +stable-x86_64-pc-windows-gnu fmt --all --check
• git diff --check
• cargo +stable-x86_64-pc-windows-gnu test -p pyrefly --lib reached 6184 passed / 5 failed; the 5 failures were shape_dsl Test took too long (> 20s) watchdog failures under the full-suite load, and each failed test passed when rerun individually