[Feature] Update mermaid support from 8.8.3 to current stable

[lunerfox]

Many new features have been added to mermaid since the last update in 2020; Right now, some of the key features within graph and stateDiagrams (Direction, If statements...etc) do not work.

[ricetech]

To add to this, the "choice" function in Mermaid State Diagrams isn't working. I just tried using the example from the Mermaid docs and it didn't show the choice at all

[nheeren]

Would love to see Entity Relationship Diagrams working too.

[ricetech]

Comments with %% also aren't working and just insert blocks as if they weren't commented out

[abnerlee]

put into #1661