`rbt patch` now has type hints all throughout. This helped catch some places where we were mixing types, leading to crashes. Notably, JSON output would crash when dealing with conflicting files represented as Unicode strings (which are expectd due to the type hints) rather than byte strings. It now uses the `Patch` class to track patches to apply, wrapped by a small `PendingPatchInfo` dictionary with the rest of the information that it needs to track. This is in preparation for using new patching logic for more SCM-driven patch application, which is in development now. As a note, the `Patch` command has been renamed to `PatchCommand`, to avoid conflicts with the `Patch` class. This will require those using the development tree to re-run `pip install -e .` to register the new entrypoint.