Use luals-stubs as the source of truth for docs, instead of maintaining

separate docs stubs

Includes introducing a cool new script to turn lua-language-server's
json output into markdown documentation.

luals-stubs/screen.lua

@@ -0,0 +1,25 @@
+--- @meta
+
+--- A distinct full-screen UI. Each screen has an associated LVGL UI tree and
+--- group, and can be shown on-screen using the 'backstack' module.
+--- Screens make use of prototype inheritance in order to provide a consistent
+--- interface for the C++ firmware to work with.
+--- See [Programming in Lua, chapter 16](https://www.lua.org/pil/16.2.html).
+--- @class screen
+local screen = {}
+
+--- Creates a new screen instance.
+function screen:new(params) end
+
+--- Called just before this screen is first displayed to the user.
+function screen:createUi() end
+
+--- Called whenever this screen is displayed to the user.
+function screen:onShown() end
+
+--- Called whenever this screen is being hidden by the user; either because a
+--- new screen is being pushed on top of this way, or because this screen has
+--- been popped off of the stack.
+function screen:onHidden() end
+
+return screen