Add neotest and overseer

lua/plugins/overseer.lua

@@ -0,0 +1,7 @@
+return {
+  "stevearc/overseer.nvim",
+  opts = {},
+  keys = {
+    { "<leader>o", "<cmd>OverseerToggle<CR>", desc = "Toggle Overseer Panel" },
+  },
+}