Fix(previews): prevent infinite loop in case of bad video file

[invario]

As noted by @Vislike (thanks!), prevent infinite looping if a video file is provided with invalid/improper atom data.
Also, fixed a calculation to ensure the moov atom is entirely contained within the downloaded data before skipping (previously only checked for the location of the beginning of the moov atom)

• Resolves: #
  feat(previews): previews for large remote files without full file download #53952

• Code is properly formatted
• Sign-off message is added to all commits
• Tests (unit, integration, api and/or acceptance) are included
• Screenshots before/after for front-end changes
• Documentation (manuals or wiki) has been updated or is not required
• Backports requested where applicable (ex: critical bugfixes)

[github-actions]

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