docs: add auth and context

docs/1.guide/2.hooks.md

@@ -15,8 +15,8 @@ Crossws provides a cross-platform API to define WebSocket servers. An implementa
 import { defineHooks } from "crossws";
 
 const hooks = defineHooks({
-  upgrade(req) {
-    console.log(`[ws] upgrading ${req.url}...`)
+  upgrade(request) {
+    console.log(`[ws] upgrading ${request.url}...`)
     return {
       headers: {}
     }
@@ -42,3 +42,73 @@ const hooks = defineHooks({
   },
 });
 ```
+
+## Authentication
+
+During the `upgrade` hook it is possible to authenticate the user before upgrading the connection. If the user is not authenticated, you can throw an error to prevent the connection from being upgraded.
+
+```ts
+import { defineHooks } from "crossws";
+
+const authToken = "Bearer myToken123";
+
+const hooks = defineHooks({
+  upgrade(request) {
+    const authHeader = request.headers.get("Authorization");
+
+    if (!authHeader || !authHeader.startsWith("Basic ")) {
+      return new Response("Unauthorized", {
+        status: 401,
+        headers: {
+          "WWW-Authenticate": 'Basic realm="Websocket Authentication", charset="UTF-8"'
+        }
+      });
+    }
+
+    const base64Credentials = authHeader.split(" ")[1];
+    const [username, password] = atob(base64Credentials).split(":");
+
+    if (username !== "myUsername" || password !== "myPassword") {
+      return new Response("Unauthorized", {
+        status: 401,
+        headers: {
+          "WWW-Authenticate": 'Basic realm="Websocket Authentication", charset="UTF-8"'
+        }
+      });
+    }
+
+    return {
+      headers: {} // Optionally return custom headers
+    };
+    },
+});
+```
+
+## Context
+
+You can store data in the `context` property of the `request` object during the `upgrade` hook or the `peer` object during the other hooks. This data will be shared in all hooks for the lifetime of the connection.
+
+> [!NOTE]
+> context can be volatile in some environments like `cloudflare-durable`
+
+```ts
+import { defineHooks } from "crossws";
+
+const hooks = defineHooks({
+  upgrade(request) {
+    request.context.data = "myData";
+  },
+
+  open(peer) {
+    console.log(peer.context.data); // myData
+  },
+
+  message(peer, message) {
+    console.log(peer.context.data); // myData
+  },
+
+  close(peer, details) {
+    console.log(peer.context.data); // myData
+  },
+});
+```