Calva should auto-connect to existing REPL instead of auto-jack-in

[seancorfield]

When auto-connect and auto-jack-in options are enabled, and REPL connect sequences provided, if you jack-in to start a REPL and then reload the VS Code window, Calva should auto-connect after the reload, instead of trying to auto-jack-in.

In general, if auto-connect (and auto-jack-in) are enabled, and an existing .nrepl-port file is present, auto-connect should be attempted first (and for bonus points, only if that fails should it auto-jack-in).

See thread on Slack for background: https://clojurians.slack.com/archives/CBE668G4R/p1727118825831329

[PEZ]

Thanks for the report. We can't really make the jack-in repl survive a reload of the VS Code window. VS Code kills it because it's spawned by the VS Code window process.

However, if the repl is started in an integrated terminal, it will survive the reload. And then we can check for an existing repl before carrying out the auto-jack-in, and do auto-connect instead.