add the window picker

plugins/nvim-window-picker/default.nix

@@ -0,0 +1,46 @@
+{lib, pkgs, ...}:{
+  extra = {
+    packages = [
+      (import ./package.nix { inherit lib pkgs; })
+    ];
+
+    config = /*Lua*/ ''
+      require('window-picker').setup({
+        hint = 'statusline-winbar', --alternative: 'floating-big-letter',
+        picker_config = {
+          statusline_winbar_picker = {
+            selection_display = function(char, windowid)
+              return table.concat({'%=', '=== ', char, ' ===', '%='})
+            end
+          },
+        },
+        highlights = {
+          statusline = {
+            focused = {
+              fg = '#E67e80',
+              bg = '#2e383c',
+              bold = true,
+            },
+            unfocused = {
+              fg = '#a7c080',
+              bg = '#2e383c',
+              bold = true,
+            },
+          },
+          winbar = {
+            focused = {
+              fg = '#E67e80',
+              bg = '#2e383c',
+              bold = true,
+            },
+            unfocused = {
+              fg = '#a7c080',
+              bg = '#2e383c',
+              bold = true,
+            },
+          },
+        }
+      })
+    '';
+  };
+}