added buffer keybinds and leetcode

lua/plugins/leetcode.lua

@@ -0,0 +1,13 @@
+return {
+    "kawre/leetcode.nvim",
+    build = ":TSUpdate html", -- if you have `nvim-treesitter` installed
+    dependencies = {
+        -- include a picker of your choice, see picker section for more details
+        "nvim-lua/plenary.nvim",
+        "MunifTanjim/nui.nvim",
+    },
+    opts = {
+      lang = "python",
+        -- configuration goes here
+    },
+}