enc: add gruvbox color scheme

lua/pcode/plugins/theme/gruvbox.lua

@@ -0,0 +1,28 @@
+return {
+  "ellisonleao/gruvbox.nvim",
+  priority = 1000,
+  opts = function()
+    local color = require("gruvbox").palette
+    return {
+      terminal_colors = true, -- add neovim terminal colors
+      undercurl = false,
+      underline = false,
+      bold = false,
+      contrast = "", -- can be "hard", "soft" or empty string
+      palette_overrides = {},
+      overrides = {
+        ["NormalFloat"] = { bg = "NONE" },
+        ["NormalNC"] = { bg = "NONE" },
+        ["MiniIndentscopeSymbol"] = { fg = color.bright_yellow },
+        ["StatusLine"] = { bg = "NONE" },
+        ["FoldColumn"] = { bg = "NONE" },
+        ["Folded"] = { bg = "NONE" },
+        ["SignColumn"] = { bg = "NONE" },
+      },
+    }
+  end,
+  config = function(_, opts)
+    vim.o.background = "dark"
+    require("gruvbox").setup(opts)
+  end,
+}