fix: nvim first boot on a fresh box — tree-sitter CLI, no luarocks, guarded local plugin

nvim-treesitter (main) hard-requires the tree-sitter CLI: new manifest
row via npm. hererocks failed compiling lua 5.1 (readline headers) for
oxocarbon's incidental rockspec: rocks disabled, the colorscheme works
without. The ~/code/nvim-ai-assist local plugin gets a cond so boxes
without the checkout skip it silently. All three found live, phase 5 VM.

private_dot_config/nvim/lua/config/lazy.lua

@@ -31,6 +31,10 @@ require("lazy").setup({
     -- version = "*", -- try installing the latest stable version for plugins that support semver
   },
   install = { colorscheme = { "tokyonight", "habamax" } },
+  -- No luarocks. The only consumer is oxocarbon's incidental rockspec, the
+  -- colorscheme works without it, and hererocks compiling lua 5.1 on a fresh
+  -- box fails on missing readline headers (live, 2026-08-23 phase 5 VM).
+  rocks = { enabled = false, hererocks = false },
   checker = {
     enabled = true, -- check for plugin updates periodically
     notify = false, -- notify on update

private_dot_config/nvim/lua/plugins/ai_assist.lua

@@ -1,6 +1,9 @@
 return {
   dir = vim.fn.expand("~/code/nvim-ai-assist"),
   name = "nvim_ai_assist",
+  -- A local checkout that only some machines have. Without the cond, every
+  -- fresh box reports "Local plugin does not exist" on first sync.
+  cond = vim.fn.isdirectory(vim.fn.expand("~/code/nvim-ai-assist")) == 1,
   lazy = false,
   cmd = { "AI", "AIHealth", "AIRefreshContext" },
   keys = {