Method call on constrained typevar emits invalid-argument-type

[sharkdp]

Consider the following example. ty currently emits two errors for the t.method() call because t.method creates a union of bound method objects where C.method and D.method are bound to T@f, respectively. Instead, attribute access should properly distribute across the union C | D and yield a union of bound method objects where C.method is bound to an instance of C, and D.method is bound to an instance of D:

class C:
    def method(self) -> int:
        return 0

class D:
    def method(self) -> str:
        return ""

def f[T: (C, D)](t: T):
    # Argument to bound method `method` is incorrect: Expected `C`, found `T@f` (invalid-argument-type)
    # Argument to bound method `method` is incorrect: Expected `D`, found `T@f` (invalid-argument-type)
    reveal_type(t.method())

https://play.ty.dev/c102d2bd-de4d-497c-9144-9f45def4196a

Related: #138