doc: add table of contents mdbook plugin

doc/README.md

@@ -11,4 +11,5 @@ For the mdbook-katex backend run:
 
 ```
 cargo install --git "https://github.com/lzanini/mdbook-katex"
+cargo install mdbook-toc
 ```

doc/book.toml

@@ -17,3 +17,8 @@ runnable = false
 [output.katex]
 
 [preprocessor.katex]
+
+[preprocessor.toc]
+command = "mdbook-toc"
+renderer = ["html"]
+

doc/src/architecture/smart_contracts.md

@@ -1,5 +1,7 @@
 # Anonymous Smart Contracts
 
+<!-- toc -->
+
 Every full node is a **verifier**.
 
 **Prover** is the person executing the smart contract function on their secret witness data.