feat: use peek.nvim instead of markdown-preview. Disable and show warning when deno is not installed

lua/lazyvim/plugins/extras/lang/markdown.lua

@@ -41,12 +41,36 @@ return {
       },
     },
   },
+
+  -- Markdown preview (requires deno)
   {
-    "iamcco/markdown-preview.nvim",
-    cmd = { "MarkdownPreviewToggle", "MarkdownPreview", "MarkdownPreviewStop" },
-    ft = { "markdown" },
-    build = function()
-      vim.fn["mkdp#util#install"]()
+    "toppair/peek.nvim",
+    enabled = function()
+      if vim.fn.executable("deno") == 1 then
+        return true
+      end
+      require("lazyvim.util").warn({
+        "`peek.nvim` requires `deno` to be installed.\n",
+        "To hide this message, install `deno` or disable the `toppair/peek.nvim` plugin.",
+      }, { title = "LazyVim Extras `lang.markdown`" })
+      return false
     end,
+    build = "deno task --quiet build:fast",
+    keys = {
+      {
+        "<leader>cp",
+        ft = "markdown",
+        function()
+          local peek = require("peek")
+          if peek.is_open() then
+            peek.close()
+          else
+            peek.open()
+          end
+        end,
+        desc = "Peek (Markdown Preview)",
+      },
+    },
+    opts = { theme = "light" },
   },
 }