theme/grubber-darker: add grubber-darker theme, which is inspired by tsodings emacs theme

modules/plugins/theme/supported-themes.nix

@@ -37,6 +37,33 @@ in {
     '';
     styles = ["dark" "darker" "cool" "deep" "warm" "warmer"];
   };
+  gruber-darker = {
+    setup = _:
+    /*
+    lua
+    */
+    ''
+      require('gruber-darker').setup({
+        -- defaults
+        bold = true,
+        invert = {
+          signs = false,
+          tabline = false,
+          visual = false,
+        },
+        italic = {
+          strings = true,
+          comments = true,
+          operators = false,
+          folds = true,
+        },
+        undercurl = true,
+        underline = true,
+      })
+      vim.cmd('colorscheme gruber-darker')
+    '';
+    styles = ["dark"];
+  };
 
   tokyonight = {
     setup = {

npins/sources.json

@@ -643,6 +643,19 @@
       "url": "https://github.com/ellisonleao/glow.nvim/archive/5d5954b2f22e109d4a6eba8b2618c5b96e4ee7a2.tar.gz",
       "hash": "11rlis4riy1w4clnkiza8x6fs8xjwsrsgfzlz2k8z041ancmrw0a"
     },
+    "gruber-darker": {
+      "type": "Git",
+      "repository": {
+        "type": "GitHub",
+        "owner": "blazkowolf",
+        "repo": "gruber-darker.nvim"
+      },
+      "branch": "main",
+      "submodules": false,
+      "revision": "98a2e141981cbd5a194a97eae024bf55af854579",
+      "url": "https://github.com/blazkowolf/gruber-darker.nvim/archive/98a2e141981cbd5a194a97eae024bf55af854579.tar.gz",
+      "hash": "0bxv33isymnbdzf71w79pfxkwi8ylhjiq3ir9ws2as1d73nnl6lv"
+    },
     "gruvbox": {
       "type": "Git",
       "repository": {