refactor: migrate treesitter config to AstroCore

lua/plugins/treesitter.lua

@@ -1,16 +1,22 @@
--- Customize Treesitter
+-- Customize Treesitter through AstroCore for AstroNvim v6
 
 ---@type LazySpec
 return {
-  "nvim-treesitter/nvim-treesitter",
+  {
-  branch = "main",
+    "AstroNvim/astrocore",
-  build = ":TSUpdate",
+    ---@type AstroCoreOpts
     opts = {
+      treesitter = {
         ensure_installed = {
           "lua",
+          "vim",
+          "vimdoc",
           "markdown",
           "markdown_inline",
-      "vim",
+        },
+        highlight = true,
+        indent = true,
+      },
     },
   },
 }