Speaker Detection & Active Video Switching

[bsenard]

Implement speaker detection logic and dynamic video selection for SIP clients with single-stream rendering (e.g. Cisco/Poly devices that display only 1 active speaker).

Tasks:

• Use LiveKit server events to detect active speakers
• Route only the active video feed to the SIP endpoint
• Handle corner cases (e.g. no one speaking, rapid speaker changes)
• Test with 3+ participants and verify smooth switching