[Accessibility]: No announcement or focus change on closing file view in ref panel

Created by: varungandhi-src

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When the Close file view button in the ref panel is clicked, there is no audio cue and the focus stays in place where the Close button was present.

There should be some announcement that the file panel was closed.
The focus should move to a sensible position, perhaps the line in the ref panel which triggered the opening of the file view (if that is available) or the file path.

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