fix: on_hud_render is not documented

doc/en/scripting/events.md

@@ -190,6 +190,12 @@ function on_hud_open(playerid: int)
 
 Called after world open.
 
+```lua
+function on_hud_render()
+```
+
+Called every frame. Used for client-side tasks such as animation and camera control.
+
 ```lua
 function on_hud_close(playerid: int)
 ```