ruff

4ef2c223 - [ty] Respect `MRO_NO_OBJECT_FALLBACK` policy when looking up symbols on `type` instances (#18312)

[ty] Respect `MRO_NO_OBJECT_FALLBACK` policy when looking up symbols on `type` instances (#18312) ## Summary This should address a problem that came up while working on https://github.com/astral-sh/ruff/pull/18280. When looking up an attribute (typically a dunder method) with the `MRO_NO_OBJECT_FALLBACK` policy, the attribute is first looked up on the meta type. If the meta type happens to be `type`, we go through the following branch in `find_name_in_mro_with_policy`: https://github.com/astral-sh/ruff/blob/97ff015c88354b5d45b52a9b1460c30978b5c29b/crates/ty_python_semantic/src/types.rs#L2565-L2573 The problem is that we now look up the attribute on `object` *directly* (instead of just having `object` in the MRO). In this case, `MRO_NO_OBJECT_FALLBACK` has no effect in `class_member_from_mro`: https://github.com/astral-sh/ruff/blob/c3feb8ce27350a4c7a560671f4668dd47761260e/crates/ty_python_semantic/src/types/class.rs#L1081-L1082 So instead, we need to explicitly respect the `MRO_NO_OBJECT_FALLBACK` policy here by returning `Symbol::Unbound`. ## Test Plan Added new Markdown tests that explain the ecosystem changes that we observe.