[sdk docs] Added mermaid ref (MystenLabs#19528)

## Description 

Was unable to build site locally to test. Trying to get mermaid graph to
render here: https://sdk.mystenlabs.com/typedoc/index.html

## Test plan 


https://sui-typescript-docs-7fcypvvd6-mysten-labs.vercel.app/typedoc/index.html

---

## Release notes

Check each box that your changes affect. If none of the boxes relate to
your changes, release notes aren't required.

For each box you select, include information after the relevant heading
that describes the impact of your changes that a user might notice and
any actions they must take to implement updates.

- [ ] Protocol: 
- [ ] Nodes (Validators and Full nodes): 
- [ ] Indexer: 
- [ ] JSON-RPC: 
- [ ] GraphQL: 
- [ ] CLI: 
- [ ] Rust SDK:
- [ ] REST API:

README.md

@@ -1,5 +1,5 @@
 <p align="center">
-<img src="https://github.com/MystenLabs/sui/blob/main/docs/site/static/img/logo.svg" alt="Logo" width="100" height="100">
+<img src="https://raw.githubusercontent.com/MystenLabs/sui/refs/heads/main/docs/site/static/img/logo.svg" alt="Logo" width="100" height="100">
 </p>
 
 # Welcome to Sui

sdk/docs/package.json

@@ -39,7 +39,8 @@
 		"nextra": "^2.13.4",
 		"nextra-theme-docs": "^2.13.4",
 		"react": "^18.3.1",
-		"react-dom": "^18.3.1"
+		"react-dom": "^18.3.1",
+		"typedoc-plugin-mermaid": "^1.12.0"
 	},
 	"devDependencies": {
 		"@types/react": "^18.3.3",

sdk/docs/typedoc.json

@@ -15,5 +15,6 @@
 	"excludePrivate": true,
 	"intentionallyNotExported": [],
 	"out": "public/typedoc",
-	"entryPointStrategy": "packages"
+	"entryPointStrategy": "packages",
+	"plugin": ["typedoc-plugin-mermaid"]
 }