Add caption and alt text generation for media

[kean]

Closes https://linear.app/a8c/issue/CMM-743/generate-alt-text-for-images and https://linear.app/a8c/issue/CMM-742/generate-captions-for-media

[dangermattic]

	1 Message
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[sonarqubecloud]

Quality Gate failed

Failed conditions
24.8% Duplication on New Code (required ≤ 10%)

See analysis details on SonarQube Cloud

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