fix(app): ensure tool calls are properly formatted with newlines in u…

[linsaftw]

…ser and assistant messages

Issue for this PR

Closes #17253

Type of change

• [ X ] Bug fix

What does this PR do?

Makes tool calls never fail because of parsing mistakes

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Screenshots / recordings

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Checklist

• [ PENDING ] I have tested my changes locally
• [ X ] I have not included unrelated changes in this PR

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[github-actions]

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