Compiler unnecessarily requires `mutating` in protocol extensions where `Self: AnyObject`

[fwcd]

Description

The compiler is unnecessarily restrictive regarding the requirement to declare protocol extension methods as mutating when it could already infer that the method is on a class.

Reproduction

Consider

protocol Wrapper {
    associatedtype Value
    var wrappedValue: Value { get set }
}

extension Wrapper where Self: AnyObject {
    func useValue(_ action: (inout Value) -> Void) {
        action(&wrappedValue) // Does not work
    }
}

This produces

mutating-object-self.swift:8:16: error: cannot pass immutable value as inout argument: 'self' is immutable
 5 | 
 6 | extension Wrapper where Self: AnyObject {
 7 |     func useValue(_ action: (inout Value) -> Void) {
   |     `- note: mark method 'mutating' to make 'self' mutable
 8 |         action(&wrappedValue) // Does not work
   |                `- error: cannot pass immutable value as inout argument: 'self' is immutable
 9 |     }
10 | }

Expected behavior

Since the following version (extending AnyObject directly) compiles:

protocol Wrapper: AnyObject {
    associatedtype Value
    var wrappedValue: Value { get set }
}

extension Wrapper {
    func useValue(_ action: (inout Value) -> Void) {
        action(&wrappedValue) // Works
    }
}

...I would expect the other variant to compile too.

Environment

swift-driver version: 1.115 Apple Swift version 6.0.2 (swiftlang-6.0.2.1.2 clang-1600.0.26.4)
Target: arm64-apple-macosx15.0

Additional information

No response