Add miele devices dynamically

[astrandb]

Proposed change

When devices are added to the account they are automatically created in HA.
If they are removed they can be deleted manually from the UI. This can also be automated, but I think it should be done when we have some more experience if there are intermittent deletions in the API.

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
• New feature (which adds functionality to an existing integration)
• Deprecation (breaking change to happen in the future)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Additional information

• This PR fixes or closes issue: fixes #
• This PR is related to issue:
• Link to documentation pull request:
• Link to developer documentation pull request:
• Link to frontend pull request:

Checklist

• The code change is tested and works locally.
• Local tests pass. Your PR cannot be merged unless tests pass
• There is no commented out code in this PR.
• I have followed the development checklist
• I have followed the perfect PR recommendations
• The code has been formatted using Ruff (ruff format homeassistant tests)
• Tests have been added to verify that the new code works.

If user exposed functionality or configuration variables are added/changed:

• Documentation added/updated for www.home-assistant.io

If the code communicates with devices, web services, or third-party tools:

• The manifest file has all fields filled out correctly.
  Updated and included derived files by running: python3 -m script.hassfest.
• New or updated dependencies have been added to requirements_all.txt.
  Updated by running python3 -m script.gen_requirements_all.
• For the updated dependencies - a link to the changelog, or at minimum a diff between library versions is added to the PR description.

To help with the load of incoming pull requests:

• I have reviewed two other open pull requests in this repository.

[zweckj]

what's the reason to switch from the pattern in your other PR (which I like, because it's still a bit shorter in each platform)?

[astrandb]

I have looked around for examples and there are pros and cons with all variants. This way the callback is triggered when data is complete in coordinator.data. I had difficulties with race conditions the other way. It could possibly have been solved but I started over and ended up with this variant that I beleive is easy to follow (at least for me - now...)