Adds an out-of-band API to the OnOff cluster

[hicklin]

This PR adds an out-of-band API to the OnOff cluster. This allows users to interact with the OnOff state machine when events or user interactions occur outside Matter.

This API provides devices two ways of interacting with the OnOffHandler.

1. Request the OnOffHandler to update its state according to the current state of the device. For example; when a user physically interacts with the device, immediately changing its state.
2. Request the OnOffHandler to issue an On or Off command. For example; a soft interaction with the device causing the device to request a change in the state. This takes advantage of the transition logic implemented by Matter, ensuring consistent behaviour across all interactions methods.

[gemini-code-assist]

Summary of Changes

Hello @hicklin, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request enhances the OnOff cluster by introducing an out-of-band API, allowing physical device interactions or external events to seamlessly integrate with the Matter state machine. This ensures that the device's Matter representation accurately reflects its real-world state, whether through direct state synchronization or by leveraging Matter's transition logic for consistent behavior.

Highlights

• Out-of-Band API for OnOff Cluster: Introduced a new API that allows external physical interactions or events to directly update or request changes to the Matter OnOff state machine, ensuring consistent behavior.
• New OutOfBandMessage Enum: Added an OutOfBandMessage enum with Update, On, and Off variants to represent different types of external notifications to the OnOff handler.
• Extended OnOffHooks Trait: The OnOffHooks trait now includes an async fn run method, enabling device-specific implementations to provide continuous out-of-band notifications to the OnOffHandler.
• Refactored OnOffHandler Logic: The OnOffHandler was updated to process these new out-of-band messages, including a dedicated update method to synchronize the Matter state with the physical device state without triggering Matter commands. Its main run loop now concurrently listens for both internal and external state changes.

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[gemini-code-assist]

Code Review

This pull request introduces an out-of-band API to the OnOff cluster, allowing for interaction with the cluster's state machine from outside of Matter, for instance, due to physical device interactions. The changes include a new OutOfBandMessage enum, updates to the OnOffHooks trait with a new run method, and modifications to the cluster's state machine to handle these new interactions. The implementation looks solid, but there are a couple of high-severity issues related to duplicate data version notifications that should be addressed. I've also pointed out some minor typos in comments.

[ivmarkov]

LGTM.