Add configurable sauna types to Saunum integration

[mettolen]

Proposed change

The Saunum Leil control unit supports three sauna type presets that can store different configurations for temperature, sauna duration, and fan duration. These presets allow you start your sauna session with different settings quickly.
Preset settings and names can only be configured on the device, but preset names are not exposed via ModBus. This feature adds sauna preset types to climate entity and makes names configurable from integration settings so users can keep names in sync with the device.

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: Add documentation to configurable sauna types to Saunum integration home-assistant.io#42743
• Link to developer documentation pull request:
• Link to frontend pull request:

Checklist

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