chore: add type annotations and resolve LSP warnings (#2555)

* chore: add type annotations to (almost) all functions

* stylua

* Add classes for symlink nodes

* Replace deprecated `@vararg`

* Move node classes to `node` module

* Fix `Symlink*` classes

* add vim and libuv runtime for luals, qualify libuv types

* add scripts/luals-check, not quite ready for CI

* additional nil checks for git/init.lua and git/runner.lua

* additional nil checks for nvim-tree.lua

* wrap vim.cmd-as-a-function calls inside functions

* vim.tbl_filter predicate returns booleans

* Revert "add scripts/luals-check, not quite ready for CI"

This reverts commit c70229cad9.

* Add `MinimalNode` class in `marks` module

* Fix various LSP warnings

* stylua

* Fix `Explorer` class, update related annotations and add necessary checks

* Add missing annotations to `live-filter`

* Add temporary aliases for `uv.*` types

* Resolve remaining LSP warnings

* Revert changes not related to internal types

* Minor adjustments

* Update doc comments style

* Minor adjustments (pt. 2)

---------

Co-authored-by: Alexander Courtis <alex@courtis.org>

lua/nvim-tree/git/utils.lua

@@ -6,9 +6,9 @@ local M = {
 }
 
 --- Retrieve the git toplevel directory
---- @param cwd string path
---- @return string|nil toplevel absolute path
---- @return string|nil git_dir absolute path
+---@param cwd string path
+---@return string|nil toplevel absolute path
+---@return string|nil git_dir absolute path
 function M.get_toplevel(cwd)
   local profile = log.profile_start("git toplevel git_dir %s", cwd)
 
@@ -60,6 +60,8 @@ end
 
 local untracked = {}
 
+---@param cwd string
+---@return string|nil
 function M.should_show_untracked(cwd)
   if untracked[cwd] ~= nil then
     return untracked[cwd]
@@ -79,12 +81,18 @@ function M.should_show_untracked(cwd)
   return untracked[cwd]
 end
 
+---@param t table|nil
+---@param k string
+---@return table
 local function nil_insert(t, k)
   t = t or {}
   t[k] = true
   return t
 end
 
+---@param status table
+---@param cwd string|nil
+---@return table
 function M.file_status_to_dir_status(status, cwd)
   local direct = {}
   for p, s in pairs(status) do