* fix(google): accept base64url in Live audio
* fix(google): normalize base64url in one pass
* fix(google): normalize base64url at every Google media boundary
* fix(google): normalize image media and avoid double music validation
* test(google): exercise URL-safe base64 fixtures
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Co-authored-by: Patrick Erichsen <patrick.a.erichsen@gmail.com>
sunlit-deng