October improvements: live captions, playback, and sign-in

TL;DR

• Live captions use the same language picker as normal projects, with up to ten source languages.
• The preview video in the editor starts faster and recovers after a connection drop.
• Signing in is faster.

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Live captions

• Pick the source language for live captions with the same picker as normal projects. You can pick up to ten source languages.

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Editor

• The preview video starts faster on new projects.
• After a connection drop the preview reloads by itself at the same position. If it still cannot load, pick Try again.

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Sign-in

• Signing in is faster.
• A sign-in that fails now shows an error, instead of a spinner that never ends.

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To try it: start a live caption session and pick your source languages.