refactor: reorganise chapters in preparation for the introduction of new sections

Author: nekename

src/SUMMARY.md

@@ -2,21 +2,26 @@
 
 [Introduction](README.md)
 
-- [Architecture](1_architecture.md)
-- [Manifest](2_manifest.md)
-- [Registration](3_registration.md)
-- [Clientbound events](4_clientbound/0_index.md)
-    - [Applications](4_clientbound/applications.md)
-    - [Deep link](4_clientbound/deep_link.md)
-    - [Devices](4_clientbound/devices.md)
-    - [Encoder](4_clientbound/encoder.md)
-    - [Keypad](4_clientbound/keypad.md)
-    - [Property inspector](4_clientbound/property_inspector.md)
-    - [Settings](4_clientbound/settings.md)
-    - [States](4_clientbound/states.md)
-    - [Will appear](4_clientbound/will_appear.md)
-- [Serverbound events](5_serverbound/0_index.md)
-    - [Miscellaneous](5_serverbound/misc.md)
-    - [Property inspector](5_serverbound/property_inspector.md)
-    - [Settings](5_serverbound/settings.md)
-    - [States](5_serverbound/states.md)
+- [Overview](overview.md)
+- [Manifest](manifest.md)
+
+---
+
+# WebSocket API reference
+
+- [Registration](api/registration.md)
+- [Clientbound events](api/clientbound/0_index.md)
+    - [Applications](api/clientbound/applications.md)
+    - [Deep link](api/clientbound/deep_link.md)
+    - [Devices](api/clientbound/devices.md)
+    - [Encoder](api/clientbound/encoder.md)
+    - [Keypad](api/clientbound/keypad.md)
+    - [Property inspector](api/clientbound/property_inspector.md)
+    - [Settings](api/clientbound/settings.md)
+    - [States](api/clientbound/states.md)
+    - [Will appear](api/clientbound/will_appear.md)
+- [Serverbound events](api/serverbound/0_index.md)
+    - [Miscellaneous](api/serverbound/misc.md)
+    - [Property inspector](api/serverbound/property_inspector.md)
+    - [Settings](api/serverbound/settings.md)
+    - [States](api/serverbound/states.md)