BUGFIX: Respect psr buffer streams and use them for string streams

[mhsdesign]

the idea is that this is more light weight instead of creating a memory resource.

see https://neos-project.slack.com/archives/C050KKBEB/p1710320388608069

Originally meant as part of https://github.com/neos/flow-development-collection/pull/3286, but we dont support buffer streams yet fully in all places.

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Checklist

• [ ] Code follows the PSR-2 coding style
• [ ] Tests have been created, run and adjusted as needed
• [ ] The PR is created against the lowest maintained branch
• [ ] Reviewer - PR Title is brief but complete and starts with FEATURE|TASK|BUGFIX
• [ ] Reviewer - The first section explains the change briefly for change-logs
• [ ] Reviewer - Breaking Changes are marked with !!! and have upgrade-instructions