bug fix: migrate room.participants to Map<string, IParticipant>

[AmilKey]

• Update IRoom interface to use Map instead of plain object
• Add IParticipant interface for type safety
• Create Participants utility module with helper functions
• Migrate all usage patterns from Object.* to Map methods
• Update React components (web/native) to use Map operations
• Fix middleware and actions to work with Map objects
• Add comprehensive test suite for utility functions
• Maintain backward compatibility through utility functions
• Add detailed migration documentation

This change improves type safety, performance, and API consistency for participant management in breakout rooms.

    /**
     * List of all the participants in the conference.
     * @type {Map<string, JitsiParticipant>};
     */
    this.participants = new Map();

https://github.com/jallamsetty1/lib-jitsi-meet/blob/master/JitsiConference.js#L164

[jitsi-jenkins]

Hi, thanks for your contribution!
If you haven't already done so, could you please make sure you sign our CLA (https://jitsi.org/icla for individuals and https://jitsi.org/ccla for corporations)? We would unfortunately be unable to merge your patch unless we have that piece :(.