chore(docs): Specify the protocol for each specification (#5418)

* chore(docs): Specify the protocol for each specification

I don't want to assume a reader knows that AsyncAPI is a websocket specification format.

* Update title in API definition introduction

fern/pages/api-definition/introduction/what-is-an-api-definition.mdx

@@ -12,7 +12,7 @@ Fern integrates with several API definition formats:
 
 <AccordionGroup>
   <Accordion
-    title="OpenAPI (Swagger)"
+    title="OpenAPI (REST & Webhook APIs)"
   >
     Formerly known as Swagger, [OpenAPI](https://swagger.io/specification/) is the most popular API definition format.
     OpenAPI can be used to document RESTful APIs and is defined in a YAML or JSON file.
@@ -102,7 +102,7 @@ Fern integrates with several API definition formats:
     ```
   </Accordion>
   <Accordion
-    title="AsyncAPI"
+    title="AsyncAPI (WebSocket APIs)"
   >
     [AsyncAPI](https://v2.asyncapi.com/docs) is a specification for defining event-driven APIs. It is used to document APIs that use 
     WebSockets, MQTT, and other messaging protocols.
@@ -156,7 +156,7 @@ Fern integrates with several API definition formats:
     
   </Accordion>
   <Accordion
-    title="Fern Definition"
+    title="Fern Definition (REST, Webhook, & WebSocket APIs)"
   >
     The Fern Definition is our take on a simpler API definition format. It is designed with **best-practices**, 
     supports **both RESTful and event-driven APIs**, and is optimized for **SDK generation**.