Add is_controller_node flag to WS node status

[kpine]

Proposed change

Add the node's is_controller_node flag to the WS node status message, which is used by the frontend to display device information. The is_controller_node flag is True when a node is the "connected" z-wave controller. The meaning of "connected controller" refers to the controller that is being controlled by the driver via the serial API. Other controllers in the network (e.g. secondary) that interact by z-wave commands are not "connected" and this flag would be false for those.

The frontend can use this flag to tailor information and actions based on whether the selected device is the connected controller or not (I have a change for that in progress). Many properties and actions for nodes are not valid for connected controllers and causes confusion with users. Common support questions are along the lines of "why doesn't my controller support z-wave plus or security?". These are examples of two properties that aren't available via the serial API and so displaying them incorrectly is misleading. With this flag the frontend is able to omit those properties.

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)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

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• This PR fixes or closes issue: fixes #
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[probot-home-assistant]

Hey there @home-assistant/z-wave, mind taking a look at this pull request as it has been labeled with an integration (zwave_js) you are listed as a code owner for? Thanks!
_{^{(message by CodeOwnersMention)}}

[MartinHjelmare]

Thanks!