docs: improve/add documentation of Lua types

- Added `@inlinedoc` so single use Lua types can be inlined into the
  functions docs. E.g.

  ```lua
  --- @class myopts
  --- @inlinedoc
  ---
  --- Documentation for some field
  --- @field somefield integer

  --- @param opts myOpts
  function foo(opts)
  end
  ```

  Will be rendered as

  ```
  foo(opts)

    Parameters:
      - {opts} (table) Object with the fields:
               - somefield (integer) Documentation
                 for some field
  ```

- Marked many classes with with `@nodoc` or `(private)`.
  We can eventually introduce these when we want to.

1 files changed, 1 insertions, 0 deletions

diff --git a/runtime/lua/vim/_meta/builtin.lua b/runtime/lua/vim/_meta/builtin.lua
index 472162ecc1..4831989e1a 100644
--- a/runtime/lua/vim/_meta/builtin.lua
+++ b/runtime/lua/vim/_meta/builtin.lua
@@ -61,6 +61,7 @@ error('Cannot require a meta file')
 ---
 --- </pre>
 
+---@nodoc
 ---@class vim.NIL
 
 ---@type vim.NIL