Scan workflow name during install.

[hjoliver]

Close #5127

Scan and report any running instances of a workflow at install time.

(Note I've used the WARNING color, but without saying "WARNING:" on grounds that already-running instances of an installed workflow might possibly indicate user error, but probably do not ... but I'm not particularly invested in this coloring!).

Check List

• I have read CONTRIBUTING.md and added my name as a Code Contributor.
• Contains logically grouped changes (else tidy your branch by rebase).
• Does not contain off-topic changes (use other PRs for other changes).
• Applied any dependency changes to both setup.cfg and conda-environment.yml.
• Tests are included (or explain why tests are not needed).
• CHANGES.md entry included if this is a change that can affect users
• Cylc-Doc pull request opened if required at cylc/cylc-doc/pull/XXXX.
• If this is a bug fix, PRs raised to both master and the relevant maintenance branch.

[hjoliver]

(Considering an integration test for this).

[oliver-sanders]

LGTM. Perhaps add in a templated cylc stop command to stop these additional runs.

Stop them with `cylc stop <id> ...`

[MetRonnie]

Tested, looking good. probably could do with a test as you've said.

Is there an easy way to include the state (running, paused etc) next to the listed workflows? Might help clarify what is meant by "active" in each case

[hjoliver]

Integration test added. Workflow status icons added.

Note this method doesn't catch instances installed with --workflow-name=other.

[hjoliver]

Should be good to go now

• restricted scan
• integration test extended
• changed CLI advice to allow easy cut-and-paste of the stop command

[hjoliver]

(Tutorial test failure unrelated)

[hjoliver]

Two approvals, going in...