fix(mcp): escape unsafe characters in error in error output

[aeitwoen]

errorResult passed newlines, terminal controls, and bidirectional formatting from provider errors or unknown tool names straight into the model's reply. That lets a failed call forge extra lines that look trusted, a nasty boundary to leave open; unsafe code points are now rendered as visible Unicode escapes instead.

[coldtea-pr-lens]

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🟢 +0 new · 🟠 ~1 changed · 🔴 -0 removed · 1 flow · 1 file · commit 56addb3

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Escaping unsafe characters in MCP errors

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