[EXPERIMENT] feat: Add video streaming support to Firebase AI Logic

[ryanwilson]

This change introduces video streaming capabilities to the Firebase AI Logic library, mirroring the existing audio streaming API.

Key features:

• A new VideoHelper class to manage camera input and frame capture.
• startVideoConversation and stopVideoConversation methods in LiveSession to control the video stream.
• Image frames are captured, scaled to a maximum dimension of 2048 pixels, and encoded as JPEGs before being sent to the backend.
• Image processing is offloaded to a background coroutine to avoid blocking the main thread and ensure smooth video streaming.
• Camera resolution selection is optimized to choose the largest available resolution for the best quality.
• Image scaling is performed efficiently using inSampleSize to minimize memory and CPU usage.

[github-actions]

📝 PRs merging into main branch

Our main branch should always be in a releasable state. If you are working on a larger change, or if you don't want this change to see the light of the day just yet, consider using a feature branch first, and only merge into the main branch when the code complete and ready to be released.

[google-oss-bot]

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[google-oss-bot]

Coverage Report ¹

Affected Products

No changes between base commit (28efb77) and merge commit (fd3279c).

Test Logs

• Base (28efb77): https://github.com/firebase/firebase-android-sdk/actions/runs/18419012807
• Merge (fd3279c): https://github.com/firebase/firebase-android-sdk/actions/runs/18421615226

1. https://storage.googleapis.com/firebase-sdk-metric-reports/tTvKxhsPgC.html

[google-oss-bot]

The public api surface has changed for the subproject firebase-ai:
error: Added method com.google.firebase.ai.type.LiveSession.isVideoConversationActive() [AddedMethod]
error: Added method com.google.firebase.ai.type.LiveSession.startVideoConversation(String,kotlin.coroutines.Continuation<? super kotlin.Unit>) [AddedMethod]
error: Added method com.google.firebase.ai.type.LiveSession.stopVideoConversation() [AddedMethod]

Please update the api.txt files for the subprojects being affected by this change by running ./gradlew ${subproject}:generateApiTxtFile. Also perform a major/minor bump accordingly.