Manage number of open editors

Open editor instances consume resources, especially if they have an associated language server process. Provide a way to list wormhole projects with open editors, order by recency of usage, and close editors that are not currently needed.

No files, tests, or entry points are named in the issue. Start by locating how wormhole tracks projects and launches or manages editor and language-server processes; define the listing, recency ordering, and safe-close behavior before identifying the tests needed to verify those outcomes.

Written by the indexing model from the issue text.