BUG: MermaidJS always crashes with SIGSEGV

[majick]

Describe the bug
All attempts to invoke the diagram tool fail. MermaidJS crashes with SIGSEGV. Because the response bubble isn't selectable there's no way to paste the failure. Screenshot attached.

To Reproduce
Steps to reproduce the behavior:

1. "Draw a circle with the diagram tool"
2. Model invokes tool
3. Tool call fails
4. Tool call repeats forever, bloating up the context.

Expected behavior
A circle.

Screenshots

Desktop (please complete the following information):

• OS: Darwin localhost 24.6.0 Darwin Kernel Version 24.6.0: Tue Apr 21 20:13:48 PDT 2026; root:xnu-11417.140.69.710.16~1/RELEASE_ARM64_T8112 arm64 arm Darwin
• Browser: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/26.5 Safari/605.1.15
• Version: Sidekick 1.0.0-rc.18 (38)

Additional context

• Network inference: llama-swap -> llama.cpp main -> Gemma-4-26B-A4B Q6_K (bf16 mmproj)
• llama-swap returns 200
• llama.cpp returns 200