Assist support AT+BVRA command?

[cobryan05]

Is your feature request related to a problem? Please describe.
When "Home Assistant" is set to my default Voice Assistant and I push the "Voice Assistant" button on my Bluetooth headset it asks me to set up Google Voice Assistant instead of activating Home Assistant Assist

Describe the solution you'd like

When Home Assistant is my default voice assistant I would like the BT Voice Assistant button to enable it

Describe alternatives you've considered, if any

Additional context

The Bluetooth device sends the AT+BVRA command to activate the voice assistant. I believe the app needs to register to receive the BVRA intent

<intent-filter>
    <action android:name="android.intent.action.VOICE_COMMAND"/>
    <category android:name="android.intent.category.DEFAULT" />
</intent-filter>

[dshokouhi]

sounds like a duplicate of either #4046 or #3981

[jpelgrom]

sounds like a duplicate of either #4046 or #3981

Not quite a duplicate, but if the fix is to register for the suggested intent we'd need to register for the intent with an activity only if HA is the active assistant. So it is likely to be an alias we can enable/disable, just like those launcher icons.