fix: Move intializion of registered llrp devices from initialize to start

[marcpfuller]

fixes: #235

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PR Checklist

Please check if your PR fulfills the following requirements:

• I am not introducing a breaking change (if you are, flag in conventional commit message with BREAKING CHANGE: describing the break)
• I am not introducing a new dependency (add notes below if you are)
• I have added unit tests for the new feature or bug fix (if not, why?)NA
• I have fully tested (add details below) this the new feature or bug fix (if not, why?)
• I have opened a PR for the related docs change (if not, why?)NA

Testing Instructions

Start Simulator
Start service
Restart the service
verify that there is no error or panic

New Dependency Instructions (If applicable)

[lenny-goodell]

LGTM