fix(meetings): update max bitrate base on resolution

[szotrabh]

COMPLETES #SPARK-746906

This pull request addresses

Update preferred bitrate on local video constraints change
Adds a localConstraintsChangeHandler that listens for ConstraintsChange events on the local video stream in transcoded (non-multistream) meetings. When video constraints change (e.g., resolution), updatePreferredBitrateKbps() is called on the media connection to adjust the preferred bitrate accordingly.

Changes
Defined localConstraintsChangeHandler in the Meeting constructor
Registered the handler on ConstraintsChange in setLocalVideoStream()
Unregistered the handler in setLocalVideoStream() and cleanupLocalStreams()

by making the following changes

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[Shreyas281299]

Source code looks good, can we add tests for the changes