Add ability to reset branch to remote

On occasion, we end up with divergent branches in our lowest shared/deployed environment. it is really cumbersome to have to drop to the OS to issue a `git reset --hard` command (in part because permissions on the OS are really restrictive). Ideally, it would do a git-fetch followed by the reset.

It would be nice if this were an option somewhere within the UI to reset the current branch to it's `origin` counterpart: either an action button when you select a local branch or maybe an input that lets you run git commands from the settings page (you could show it only in expert mode)

This is more of a convenience request than anything else.

Start by locating the UI entry point for selecting local branches and the existing fetch or branch actions. Determine how a reset to the branch's origin counterpart can be exposed safely, then verify that fetching and resetting produce the expected branch state in the shared environment.

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