Ensure platform setup for all AVM FRITZ!SmartHome devices

[mib1185]

Proposed change

In case when one platform setup is delayed (example #105346 (comment)) the coordinator.new_devices might already be cleared by a meanwhile further coordinator data update run.
To ensure each platform is at proper set up, we statically run _add_entities with the whole bunch of devices during setup, but during coordinator update listener, we only consider the coordinator.new_devices property.

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
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• Breaking change (fix/feature causing existing functionality to break)
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Additional information

• This PR fixes or closes issue: fixes AVM FRITZ!SmartHome sensor entities of Fritz DECT 200 are missing after update to 2023.12 #105346
• This PR is related to issue:
• Link to documentation pull request:

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[home-assistant]

Hey there @flabbamann, mind taking a look at this pull request as it has been labeled with an integration (fritzbox) you are listed as a code owner for? Thanks!

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[mib1185]

Hi @elupus sorry to "bother" you with this PR, but it is a fix for #103859 where we had worked together on it.