md -> mmd

usage:

```sh
nix-shell -p mermaid-cli --command 'mmdc -i data-model.mmd -o
data-model.svg -b transparent'
```

architecture-docs/data-model.mmd

@@ -1,8 +1,3 @@
-<!-- usage: `nix-shell -p pandoc -p mermaid-filter --command 'pandoc data-model.md -o data-model.html -F mermaid-filter'` -->
-
-# fediversity entity relations
-
-```mermaid
 ---
 title: Fediversity entity relations
 ---
@@ -27,4 +22,4 @@ erDiagram
     application ||--o{ version : follows
     application ||--o{ script : runs
     deployed }|--o{ version : follows
-```
+    script }o--|| token : uses