feat: add transcript normalization + m4a audio format support

docs: clarify alternatives for deprecated fields

feat: deprecate `BatchRecognizeFileResult.uri` in favor of `cloud_storage_result.native_format_uri`

feat: deprecate `BatchRecognizeFileResult.transcript` in favor of `inline_result.transcript`
PiperOrigin-RevId: 577926708

Source-Link: googleapis/googleapis@37e816b

Source-Link: https://github.com/googleapis/googleapis-gen/commit/e12bd7bdbbb9d2e418a922075d23f77a8c1e7485
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