Implement dehumidifier

[filmackay]

This pull request introduces support for De'Longhi Dehumidifiers. The changes separate device handling by type (air conditioner, heater, dehumidifier), add new platforms for dehumidifier support, and improve code clarity and maintainability. Additionally, the documentation is enhanced with a comprehensive overview, and configuration and polling intervals are refined.

Device architecture and coordinator routing:

• Refactored device setup in __init__.py to sort discovered devices into separate coordinator lists by type (airconditioner_coordinators, heater_coordinators, dehumidifier_coordinators). All platform files now use these lists, improving clarity and making it easier to add device-specific logic. [1] [2] [3] [4] [5] [6]

Dehumidifier support:

• Added a new humidifier.py platform for dehumidifier entities, implementing the DeLonghiDehumidifier class with support for on/off, mode, and humidity setpoint, and exposing a device mode mapping for use in other platforms.
• Implemented a new binary_sensor.py platform for dehumidifier alarm states (tank full, filter warning), using bitmask extraction from the device's alarm_state property.
• Enhanced the select.py platform with a DehumidifierModeSelect entity for changing dehumidifier modes, using the shared device mode mapping. [1] [2]
• Updated sensor.py to add dehumidifier-specific sensors using a new set of entity descriptions.

Configuration and constants:

• Introduced constants for OEM model names (OEM_MODEL_HEATER, OEM_MODEL_DEHUMIDIFIER) and updated code to use these for device type checks.
• Increased the default polling interval from 5 to 15 seconds to reduce API load.

Documentation and developer experience:

• Added a detailed OVERVIEW.md describing the integration's purpose, architecture, complexity, and key files, aiding onboarding and maintenance.
• Added Docker compose for easier debugging & testing.

Other improvements and fixes:

• Fixed minor issues in config_flow.py related to options flow initialization. [1] [2]
• Ensured translations are preloaded at setup to support frontend UI translation requests. [1] [2]

Resolves #2.

[filmackay]

I am finding the humidity numbers are non-sensical when, the fan is not running. Temperature seems reasonable. I am thinking of making the humidity publish as unknown when the dehum unit is OFF. Ideally it would wait a minute after ON before publishing humidity numbers.

Thoughts/feedback?

[anobl]

confirming this fixed my issues

[filmackay]

Any thoughts @philm5?