If Bitcoin's already running, check if it's on the target version

Before launching Bitcoin, check if it's already running:
- if Bitcoin isn't running do the status quo (launch bitcoin)
- if Bitcoin is running, check the version
- if it's on the target version, don't launch it again
- if it's not on the target version, stop the current pid via `bitcoin-cli`, wait for it to stop, then do the status quo (launch bitcoin).

Locate the Shell code path that launches Bitcoin and trace how its process status and target version are determined. Implement the requested cases: launch when absent, leave a matching version running, or stop and wait for a mismatched version before launching; verify each case against the issue requirements.

Written by the indexing model from the issue text.