[FR]: Matcher for absl::StatusOr and std::expected

### Does the feature exist in the most recent commit?

No

### Why do we need this feature?

Working on code bases that use C++23, std::expected is used extensively for error handling.
Having a _matcher_ for it would help on testing.

### Describe the proposal.

Similar to **VariantWith()** add a matcher that uses std::expected and it supports its monadic features.
Would be nice to check for compiler features.

### Is the feature specific to an operating system, compiler, or build system version?

As of this writing, the big 4 compiler library features support it.

Start by reviewing the existing VariantWith() matcher and the project's compiler-feature support, then compare the APIs of absl::StatusOr and C++23 std::expected. Done means providing a matcher for the proposed types, including their monadic features, with appropriate compiler feature checks.

Written by the indexing model from the issue text.