Update sphinxcontrib-mermaid from 0.9.2 to 2.0.0

Author: pyup-bot

docs/requirements.txt

@@ -5,7 +5,7 @@ sphinx-autodoc-typehints==3.6.3
 furo==2025.12.19
 sphinxext-opengraph==0.13.0
 sphinx-copybutton==0.5.2
-sphinxcontrib-mermaid==0.9.2
+sphinxcontrib-mermaid==2.0.0
 
 # auxiliary
 typing-extensions==4.12.2