design mutex HBI feature for use in dynamic analysis

let's discuss the requirements and sketch a design for how this feature should look and act. the idea is to represent a mutex artifact that is manipulated during a dynamic analysis session.

this should include how the rule syntax changes, the format of the feature and properties of the feature, and at least two example rules showing how the feature would be used.

once we're happy with the design, then lets plan for opening a standalone PR with the Registry feature.

open questions include:
- how to represent operations, like create/acquire
- how to represent namespace versus path
- how to combine all the above with logic, or not. and how this affects rule syntax

No files, tests, or entry points are named. Start by reviewing the existing rule syntax and feature representations, then compare them with the requested mutex operations, namespace/path handling, and logic questions. Done means a documented design, updated syntax definition, feature format and properties, and at least two example rules.

Written by the indexing model from the issue text.