types and docs for integrations_dir

doc/nvui.txt

@@ -623,6 +623,16 @@ It's preferred to put the dofile code in your plugin's config func
     end
  }
 <
+To include custom integrations, use the `base46.integrations_dir` option to
+define a module name that contains the custom integration files. Loading
+from the custom module location will only be tried if there is no matching
+official integration.
+>lua
+ M.base46 = {
+   integrations_dir = "foo.integrations",
+   integrations = { "dap", "hop", "customname" },
+ }
+<
 ------------------------------------------------------------------------------
 6.5 Local themes		                      *nvui.base46.local_themes*
 

lua/nvconfig.lua

@@ -4,6 +4,7 @@ local options = {
     theme = "onedark", -- default theme
     hl_add = {},
     hl_override = {},
+    integrations_dir = nil,
     integrations = {},
     changed_themes = {},
     transparency = false,

scripts/update-nvchad-types.lua

@@ -87,6 +87,9 @@ local gen_highlights = function()
       end
     end
   end
+  -- allow string type to keep completion through enum values
+  -- while avoiding linter warnings for custom integrations.
+  table.insert(contents, string.format "---| string")
 
   for name, integration in vim.spairs(hlgroups) do
     if string.sub(name, 1, 1) == "@" then