Fix nvim-treesitter config: use explicit config fn instead of main

lazy.nvim's `main` shorthand resolves the module before the plugin is
fully loaded, causing 'nvim-treesitter.configs not found' on first run.
Explicit config function defers the require until setup time.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

shared/.config/nvim/init.lua

@@ -258,8 +258,8 @@ require('lazy').setup({
   {
     'nvim-treesitter/nvim-treesitter',
     build = ':TSUpdate',
-    main  = 'nvim-treesitter.configs',
-    opts  = {
+    config = function()
+      require('nvim-treesitter.configs').setup({
         ensure_installed = (function()
           local t = { 'bash', 'json', 'lua', 'luadoc', 'markdown', 'markdown_inline', 'vim', 'vimdoc', 'yaml' }
           vim.list_extend(t, _lang.parsers or {})
@@ -268,7 +268,8 @@ require('lazy').setup({
         auto_install = true,
         highlight    = { enable = true },
         indent       = { enable = true },
-    },
+      })
+    end,
   },
 
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