Fix inference when Any is passed as a type object

[yhuikzdtguioaert]

Fixes #20859.

Recent typeshed versions represent typing.Any as a class at runtime. When that value was passed to a parameter of type type[T], constraint inference extracted its internal typing.Any instance literally instead of treating it as the dynamic Any type. This produced a type that displayed as Any but was not semantically Any, so assert_type(foo(Any), Any) reported the confusing Any versus Any error.

This normalizes the typing.Any instance while inferring constraints from type objects. Other class objects keep their existing instance type. The regression test uses a class-based typing.Any fixture and checks both assert_type and the revealed inferred type.

Validation:

• Regression test: 1 passed
• check-classes.test: 610 passed, 1 xfailed
• mypy self-check: 196 source files clean
• pre-commit lint suite: passed
• Full pytest run: 13,907 passed, 653 skipped, 11 xfailed; 33 unrelated mypyc runtime tests failed because the Windows linker could not create the generated librt .exp file (LNK1104).

[github-actions]

According to mypy_primer, this change doesn't affect type check results on a corpus of open source code. ✅