fix: scheduler host address passed to runtime

[mikeee]

Description

Refactors the way scheduler-host-address is handled and adds the arg to enable standalone mode runs.

The scheduler can now be initialised by flag with the run command, if an older runtime is installed there is some janky logic to not pass the flag. Instead, a notice is displayed.

Issue reference

We strive to have all PR being opened based on an issue, where the problem or feature have been discussed prior to implementation.

Please reference the issue this PR will close: #1420

Checklist

Please make sure you've completed the relevant tasks for this PR, out of the following list:

• [x] Code compiles correctly
• [ ] Created/updated tests
• [ ] Extended the documentation