Merge branch 'develop' into next

* develop:
  chore: Remove circular dependency
  Update docs
  docs: Add frontmatter config demos
  docs: Add frontmatter config docs
  fix: XSS vulnerability
  chore: Minor typo fixes
  chore: Add test with both frontmatter and directive
  Update docs
  feat: Add support for config in frontmatter
  chore: Fix type in assignWithDepth
  refactor: Move `sanitizeDirective` into `addDirective`
  refactor: Rename and cleanup `directiveSanitizer`

demos/er.html

@@ -21,6 +21,8 @@
     <pre class="mermaid">
       ---
       title: This is a title
+      config:
+        theme: forest
       ---
       erDiagram
         %% title This is a title

demos/flowchart.html

@@ -123,6 +123,13 @@
 
     <h3>flowchart</h3>
     <pre class="mermaid">
+    ---
+    title: This is another complicated flow
+    config:
+      theme: base
+      flowchart:
+        curve: cardinal
+    ---
     flowchart LR
     sid-B3655226-6C29-4D00-B685-3D5C734DC7E1["