Add GenMedia Live - real-time multimodal creation with Gemini Live, Gemini Nano Banana and Veo

[WafaeBakkali]

Summary

This PR adds GenMedia Live, a sample app demonstrating real-time multimodal creation by extending Gemini Live capabilities to image and video generation through function calling.

What it does

GenMedia Live combines Gemini Live's real-time streaming with:

• Gemini 3 Pro Image for image generation and editing
• Veo for video generation
• ffmpeg for frame extraction and video combining

User can use natural voice to;

• Generate images from descriptions or edit existing ones
• Create videos from text prompts or animate images
• Create short movies by combining multiple video clips
• Ask questions about what they show on camera or upload
• Extract frames from videos for further editing

Description

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Fixes #<issue_number_goes_here> 🦕