docs: add mermaid docs (#6971)

* docs: add mermaid docs

* fix link

* add development.mdx

* add codebase

* add parseEdge

* add subgraph

* convertors

* tweaks

* structure the codebase

* add docs for new diagram type

* decouple docs for flowchart parser

* fix broken links

* use diagram instead of chart

* revert package.json

* tweaks

* point root folder of mermaid-to-excalidraw to installation

* remove installation from sidebar children

* fix link

* update flowchart parser diagram

* update parser overview diagram

* update more diagrams

* remove note about change in element stroke

* update diagram

* increase size limit for excalidraw production bundle

* tweaks

* add link

* move codebase after introduction

* dummy

---------

Co-authored-by: dwelle <luzar.david@gmail.com>

dev-docs/docs/@excalidraw/mermaid-to-excalidraw/installation.mdx

@@ -0,0 +1,42 @@
+# Installation
+
+`@excalidraw/mermaid-to-excalidraw` is published to npm. This library is used in [excalidraw](https://excalidraw.com) to transform mermaid syntax to Excalidraw diagrams.
+
+Using `npm`
+
+```bash
+npm install @excalidraw/mermaid-to-excalidraw
+```
+
+Using `yarn`
+
+```bash
+yarn add @excalidraw/mermaid-to-excalidraw
+```
+
+## Usage
+
+Once the library is installed, its ready to use.
+
+```js
+import { parseMermaidToExcalidraw } from "@excalidraw/mermaid-to-excalidraw";
+import { convertToExcalidrawElements}  from "@excalidraw/excalidraw"
+
+try {
+  const { elements, files } = await parseMermaid(diagramDefinition, {
+    fontSize: DEFAULT_FONT_SIZE,
+  });
+  // currently the elements returned from the parser are in a "skeleton" format
+  // which we need to convert to fully qualified excalidraw elements first
+  const excalidrawElements = convertToExcalidrawElements(elements);
+
+  // Render elements and files on Excalidraw
+} catch (e) {
+  // Error handling
+}
+```
+
+## Playground
+
+ Try it out [here](https://mermaid-to-excalidraw.vercel.app)
+