feat: Unified Docs

[simsaens]

In order to support native documentation rendering, and documentation as source-of-truth for all editor behaviour, we have to:

• Ensure the RST contains all parameter types and return types
• Ensure the RST structure is grouped and has the correct hierarchy
• Add metadata relating to editor roles for API (for example, informing the editor that the color picker should be shown for style.fill)
• Add metadata relating to symbol classes for API. By default this will be api-call (Codea API) but we distinguish Lua-api in order to syntax highlight Lua built-in methods correctly
• Add metadata for symbol visibility. Some types are private and should not be exposed to Codea documentation, but are necessary for autocomplete
• Ensure that table types with known fields have a private representation documenting their fields (objc.insets(), viewer.safeArea)
• Ensure enums that group together belong to the same symbol group (STANDARD, FULLSCREEN, FULLSCREEN_NO_BUTTONS). This is for a future editor affordance