docs: Add documentation for zod type provider (#4456)

Co-authored-by: Frazer Smith <frazer.dev@outlook.com>

docs/Reference/Type-Providers.md

@@ -11,15 +11,16 @@ keep associated types for each schema defined in your project.
 
 Type Providers are offered as additional packages you will need to install into
 your project. Each provider uses a different inference library under the hood;
-allowing you to select the library most appropriate for your needs. Type
+allowing you to select the library most appropriate for your needs. Official Type
 Provider packages follow a `@fastify/type-provider-{provider-name}` naming
-convention.
+convention, and there are several community ones available as well.
 
 The following inference packages are supported:
 
 - `json-schema-to-ts` -
   [github](https://github.com/ThomasAribart/json-schema-to-ts)
 - `typebox` - [github](https://github.com/sinclairzx81/typebox)
+- `zod` - [github](https://github.com/colinhacks/zod)
 
 ### Json Schema to Ts
 
@@ -91,6 +92,12 @@ See also the [TypeBox
 documentation](https://github.com/sinclairzx81/typebox#validation) on how to set
 up AJV to work with TypeBox.
 
+### Zod
+
+See [official documentation](https://github.com/turkerdev/fastify-type-provider-zod)
+for Zod type provider instructions.
+
+
 ### Scoped Type-Provider
 
 The provider types don't propagate globally. In encapsulated usage, one can